REPRODUCTION in Algae by Jamiublog

REPRODUCTION AND LIFE CYCLE IN ALGAE

Introduction

Previously we learn that algae vary in size from small microscopic
unicellular forms like chlamydomonas to large macroscopic
multicellular forms like Polysiphonia. The multicellular forms show
great diversity in their organization and include filamentous,
heterotrichous, thalloid and polysiphnoid forms. In this unit we will
discuss the types of reproduction and life cycle in algae taking suitable
representative examples from various groups. Algae show all the three
types of reproduction vegetative, asexual and sexual. Vegetative
method solely depends on the capacity of bits of algae accidentally
broken to produce a new one by simple cell division. Asexual methods
on the other hand involve production of new type of cells, zoospores.
In sexual reproduction gametes are formed. They fuse in pairs to form
zygote.
Zygote may divide and produce a new thallus or it may secrete a thick
wall to form a zygospore.

3.1 TYPES OF REPRODUCTION
Reproductive processes found in various groups of algae can be broadly divided into three types: vegetative, asexual and sexual methods.
Vegetative Reproduction
The most common type of reproduction in algae is by binary fission. In
unicellular prokaryotic algae like Anacystis it is the only method of
reproduction found in nature. In filamentous and multicellular forms,
the algae may get broken accidentally into small pieces, -each
developing into a new one. The above methods of propagation are known
As vegetative reproduction.
• Asexual Reproduction
When vegetative reproduction takes place through specialized cells
(other than sex cells), it is descried as asexual reproduction.
Anabaena and Nostoc
The cells accumulate food materials; develop thick walls to become
spores or akinetes (Fig. 3.1). Akinetes can withstand dryness (lack of
water) and high temperature for a long time, but when conditions are
suitable they germinate to form new filaments.

Anabaena showing akinetes.

Ulothrix
Filamentous algae (like Ulothrix) may reproduce by producing motile cells called zoospores (Fig. 3.2). The protoplast of a single cell divides many times by mitosis to produce several zoospores.

Formation of zoospores in Ulothrix

Each zoospore has 2-4 flagella with which it swims for sometime and
then settles by its anterior end. It subsequently divides into a lowerEach zoospore has 2-4 flagella with which it swims for sometime and
then settles by its anterior end. It subsequently divides into a lowercell which becomes the holdfast and the upper cell which by further
divisions becomes the vegetative filament. Zoospores are produced in
other algae also.
Asexual reproduction in other algae is described below.
Chlamydomonas
Although this is a unicellular motile algae but it produces zoospores.
The parent cell divides inside the cell –envelop and each daughter cell
develops two flagella each. These zoospores look exactly like the parent
cell except they are smaller in size. When the zoospores are fully
developed the parent cell wall dissolves, releasing them free into the surrounding water (Fig.3.3)

Fig. 3.3 :Formation of zoospores and palmella stage in Chlamydomonas

Sometimes when there is less water outside, zoospores may lose
flagella and round up. These non-motile spores are called
aplanospores which develop into thick walled hypnospores.
On moist soil when zoospores can not be released due to lack of free
water, they get embedded within a gelatinous material formed from
parent cell wall. Such cells do not have flagella but whenever they
become flooded with water they develop flagella and swim away in the water These gelatinous masses containing thousands of non-motile
cells are known as palmella stage of Chlamydomonas.
Oedogonium Zoospores are produced singly in a cell. Each has one
nucleus and a crown of flagella at the apex.
Many zoospores are produced from a single cell, as in Ulothrix. They have single nucleus and 2-4 flagella. Ectocarpus
Zoospores are produced in sporangia which are of following two types:
• Plurilocular Sporangia: The sporangium is made up of many
cells and several biflagellate zoospores are produced (Fig. 3.4).
• Unilocular Sporangia: The sporangium is made up of one cell
which produces single biflagellate zoospore (Fig. 3.4)

Fig. 3.4: Unilocular and Plurilocular sporangia of Ectocarpus

3.1.3 Sexual Reproduction
Sexual reproduction in algae like in other organisms involves the
fusion of two cells from opposite sex called gametes, resulting in the
formation of a zygote. Some basic features of this method of
reproduction are as follows:
Gametes are always haploid and may or may not be different in
morphology. If both the sex cells look alike, they could be male called
plus (+) or female called minus (-) mating types of strains. Gametes
can fuse only when one is plus and the other is minus.
Both of them + and – may be produced by a single parent. This is
called monoecious or homothallic condition. When they come from
different plus or minus thallus types it is called dioecious or
heterothallic condition.
There are three types of gametic fusion (Fig. 3.5).
a. Isogamy: When both the gametes are of the same size and
morphology.
b. Anisogamy: The two gametes are distinctly different in size or
shape, the larger of the two is minus (female) type.
c. Oogamy: The female gamete, egg or ovum is big in size and has no
flagella hence it is non-motile. Male gametes are flagellated and
highly motile. They are also known as antherozoids,
spermatozoids or sperms.
The male gametes are attracted by the female cells because of special hormones called gamones (a violatile hydrocarbon) produced by them. Fusion of the gametes leads to the formation of a zygote. If the conditions are unsuitable for growth, the zygote may develop a thick wall and become a resting zygospore. Gametes being haploid, are produced by mitosis in a haploid thallus. If the thallus is diploid as in Fucus the reproductive cells undergo meiosis or reduction division to form gamete.

Fig. 3.5: Three types of gametic fusion-isogamy, anisogamy and oogamy.

In haploid thallus, after the fusion of gametes, the diploids zygote
undergoes meiosis during germination. However, in diploid algae a
zygote may divide mitotically and give rise to a diploid thallus (Fucus).
Both haploid and diploid thallus are found in Ulva. They look very
similar in size and shape.

3.2 REPRODUCTION AND LIFE CYCLE
We have given above the basic modes of reproduction in algae. Now we take up some specific algal types to illustrate their life cycle in nature. It is to be noted that the life cycle of an alga is very much controlled by environmental factors like temperature, light, seasons, and availability of nutrient, and also salinity, wave action and periodicity of tides in the case of marine forms. Observations made by people during different times from various geographical locations and sometimes experimentally studied under controlled conditions, give us fairly comprehensive if not a complete picture of the life cycle of an alga.
3.2.1 Chlamydomonas
Sexual reproduction in this alga shows all the three different types
depending on the species (Fig. 3.6). Isogamy is found in C. reinhardii, C. gynogama and C. media.

Fig. 3.6 :Sexual reproduction in Chlamydomonas: Isogamy, anisogamy and oogamy.

Isogamy is of two types:
In clonal population:(cells obtained by the repeated divisions of a
single parent cell) fusion may take place between gametes which are
homothallic or in self compatible strains. For example, fusion occurs
between any two cells of C. gynogama and C. media.
In C. moewusii and C. reinhardii fusion of gametes can take place only
when they come from two different unrelated (heterothallic, self
incompatible) strains.
In many isogamous species the parent cell may divide to produce 16 to
64 biflagellate gametes while in some the adult cells themselves may
directly behave as gametes and fuse.
Anisogamous form of gametic fusion is found in C. braunii. A female
cell divides and produces four large cells. Each of these cells have two
flagella but are less active. The male cells are about 8 in number but
smaller in size.
Oogamy is the advanced type of sexual reproduction found in C.
coccifera. A parent cell discards its flagella and directly becomes a non-
motile egg or ovum. While male parent cell by repeated divisions
produces sixteen male gametes. These are biflagellate and highly
motile.
The process of gametic attraction, fusion and related phenomena have
been studied in some detail in the laboratory. Under proper light
condition and carbon dioxide concentration, production of gametes can
be initiated by nitrogen starvation. The formation of male or female
gametes (even in the case of isogamy) is attributed to the varying
concentration of gamones produced by them. The attraction between
gametes was found due to the presence of glycosidic mannose at the
tips of the flagella of one strain which in a complementary way binds
with the substance present in the flagella of the gamete of the opposite
stain. Once this sticking of the flagella of plus and minus gametes
takes place, flagella twist about each other bringing the anterior ends
of the gametes close. This is followed by cellular and nuclear fusion.
The zygote secrets a thick wall and accumulates large amount of food
materials like starch. Lipids and orange – red pigments. It is now
known as zygospore which remains dormant till the environmental
conditions are favourable for its germination
It has been shown that during germination of zygospore meiosis takes
place followed by mitosis resulting in haploid Chlamydomonas cells.
Life Cycle
Chlamydomonas is unicellular, haploid and reproduces asexually
many times by forming zoospores. Under unfavourable environmental
conditions it produces gametes which fuse to form diploid zygospore.
During germination reduction division takes place and haploid cells
are formed (Fig. 3.7).
Chlamydomonas is of great interest to biologists. Its study has brought
to light several interesting features of biological importance, some of
which are listed below.
i Presence of DNA in the chloroplasts of the alga
ii Presence of cytoplasmic genes
iii Production of genetic mutations – affecting nutrition,
photosynthesis and production of mutants without flagella or cell
wall.
iv Dicovery of gamones and their role in sexual reproduction.
v Presence of isogamy, anisogamy and oogamy in a single genus.
vi Control of reproduction by environmental conditions.

Fig. 3.7: Life cycle of Chlamydomonas

• Alternation of Generations
The type of life cycle of an organism in which reproduction
alternates with each generation between sexual reproduction and asexual reproduction is called alternation of generations. The two
generations are termed as gametophytic and sporophytic
generations. The gametophytic generation is haploid(n) and the
sporophytic generation is diploid(2n)
The fusion of two gametes(n) results in zygote(2n) which on
germination forms the plant / thallus called sporophyte. The
sporophyte in turn produces haploid spores by meiosis. When a
spore germinates it develops into gametophyte which bears male
or female gametes or both on the same plant / thallus.
In some bryophytes the gametophytic generation is more
conspicuous. While in ferns the sporophytic generation is more
prominent. In angiosperms main plant body is sporophyte and
the gametophytic generation is reduced to a few cells. You will see
that all type of situations prevail in algae. In some algae
gametophyte is prominent while in others sporophyte is
prominent.
3.2.2 Ulothrix
Sexual reproduction takes place by means of isogamous,
biflagellate.
Fusion takes place only between plus and minus mating types.
The gametes are from different filaments (heterothallic). The
zygote develops a thick wall and remains dormant till the
conditions are favourable for germination. When conditions
become favourable meiosis takes place and 4 – 16 haploid
zoospores are produced which settle down and give rise to
vegetative filaments (Fig. 3.8) It has been found that Ulothrix produce gametes when grown
under long day conditions while short day conditions initiate the
formation of zoospores.

Life Cycle
Look at Fig. 3.8 : showing the life cycle of Ulothrix.
Which is the diploid stage of the algae?
The thallus of Ulothrix is haploid and the diploid stage is
represented by the zygote only.
We would like to draw your attention to the fact that in some
species (U. speciosa, u. flcca and and in U. implexa) the zygote
develops into an independent, unicellular, thallus which is
diploid in nature. It produces zoospores asexually by meiosis. The
zoospores develop into haploid filaments.
Thus in Ulothrix two types of life cycles can be distinguished:
Haplobiontic:
The thallus is haploid and only the zygote is diploid e.g. U.
zonata?
Diplobiontic:
In diplobiontic cycle, the alga consists of a haploid thallus that
produces gametes and a diploid unicellular stalked thallus which
produces zoospores after meiotic division. The two generations –
haploid and diploid, alternate with each other. (alternation of
generations). Because the two thalli are very different in size and
morphology it is known as heteromorphic, diplobiontic life
cycle.

Fig. 3.8: Life cycle of Ulothrix

Fucus
uocus has advanced type of reproductive structure, termed as receptacles, which are swollen at the tips of branches (Fig. 3.9 A) Distributed over the surface of each receptacle are small pores, known as ostioles which lead into the cavities, called conceptacles (Fig. 3.9B). Each conceptacle may produce only eggs, only sperms or as in some cases both. A thallus may be unisexual – either having male receptacle or only female ones.

Fig. 3.9 :Fucus : A) Structure of thallus, B) Enlarged receptacle

At the base, inside the conceptacle is a fertile layer of cells which
develops into oogonia (Fig. 3.10). Each oogonium has a basal
stalk cell and an upper cell which undergoes reduction division
and produces eight haploid eggs (Fig. 3.10C and D). These are
liberated in the conceptacle (Fig. 3.10E). Some of the cells inside
the conceptacle produce unbranched multicellular hairs called
paraphyses which emerge out of the ostiole as tufts.

Fig. 3.10: Fucus A) T. S. through female conceptacle showing oogonia, B) T.
S. through male conceptacles showing antheridia, C) structure of an
oogonium, D and E) formation and liberation of eggs.

Fig. 3.11: Formation and developmental stages of a zygote

Antheridia are produced on branched paraphyses inside the
concptacle ( Fig. 3.10B). Each antheridium is like a unicellular
sporangium which divides meiotically and then by further
divisions produced 64 haploid sperms. The biflagellate sperm has
a longer flagellum pointing backwards and a shorter one
projecting towards the front. It has a single chloroplast and a
prominent orange eye spot
The release of the gametes is connected with the sea tides. At low
tide, Fucus fronds shrink due to loss of water, and when such
fronds are exposed to an on coming tide, the eggs and sperms are
released into the surrounding sea water.
The egg of Fucus are known to attract sperms (Fig. 3.11 A and B)
by secreting a gamone. Immediately after fertilization a all is
secreted around the zygote. It has been shown that unfertilized
eggs can develop into germlings parthenogenetically if treated
with dilute acetic acid.
The diploid zygote germinates by producing a rhizoidal outgrowth
on one side. It is later cut by wall formation to form a lower
rhizoidal cell and apical cell (Fig. 3.11 C) which by further
divisions (Fig. 3.11 D and E) gives rise to the Fucus fronds.
4.0 CONCLUSION
Reproduction in algae could be by vegetative method (binary
fission), asexual through specialized cells or sexual by fusion of
two cells from opposite sex called gametes.
The life cycles of Chlamydomonas, Ulothrix and Ficus were
discussed. There are other genera in this group. It should be
noted that algae also exhibit alternation of generations in their life
cycles.

5.0 SUMMARY
• Reproduction in algae is by asexual and sexual methods.
• Asexual method involves fission of cells are regeneration of
new ones
• Sexual method involves fusion of male gamete and female
gamete resulting in the formation of a zygote.
• The life cycle in algae demonstrates clearly a marked
alternation of generations especially in the higher forms like
Ulva, Laminaria and Ficus.

REFERENCES
• Dutta A.C. (1981). Botany for degree students.
Oxford University Press. 909p.
IGNOU. (1991). Indra Gandhi Nationl Open University. Plant
Diversity – Algae.
• Dutta A.C. (1981). Botany for degree students.
Oxford University Press. 909p.
• IGNOU. (1991). Indra Gandhi Nationl Open University. Plant
Diversity – Algae.
Dutta: A. C. (1981). Botany for degree students. Oxford University Press
909p.
• IGNOU. (1991). Indra Gandhi National Open University. Plant Diversity.

FG have made provision for minimum wages of 30,000

Apl
30,000 minimum wage

Federal government will implement the minimum wages of 30,000 said by the secretary to the government of federation Mr boss mustapha.

Addressing the reporters on Thursday in Abuja that government was committed to the implementation..27,000 to 30,000 by the house of Representatives.

Look at where we took it from 18,000 as a minimum wages..Mr mustapha said ..what is before the house representative is 30,000 though we recommended 27,000..what ever comes out of it ..the president has sufficient capital in his integrity to own whatever Nigeria decide …he assured people.

Roma fan jail for attacking Liverpool fans

Italian football fan jail for three and half years on Thursday after admitting for assaulting a Liverpool supporters before the premiere league game living the victim with a catastrophe of head injuries.

Simeone mastrelli pleaded unlawful guilty age 30 from for Rome italy .. having meciliously inflicted a severe body harm on sean cox outside the anfied stadium on April 24 before their match with Italian side Roma.

Irish national cox suffered a severe brain injury as a result of the attack and still recovering after 4 and half in neurological unit.

Mastrelli knocked cox with a heavy blow on the face as he led a group of “utras” whom some of them having belt as their weapon.

Cox daughter Shauna 20 read out statement in court of Preston crown as mastrelli watch in Northwest England.

Before this brutal viscious attack my dad was a fit man, a man of integrity with a huge passion for life that who represents everything which is good.. she said.

This violent and unprovoked attacked left dad in a dire situation

His future is uncertain we don’t know how he Will progress that really frightened us.

Mastrelli was arrested in Italy by European arrest warrant before being extradited to Britain.

Judge brown said to mastrelli that I had no doubt in my mind that you went in group to the stadium to sort out Liverpool supporters in doing so you have destroy the life a innocent man and his family.

This was on any view .. a dreadful offence. And it has a profound impact on Mr cox and his family.

Another Roma fan, fillippo was last year jail for three years for violent disorder.

Femi Adebayo strike a POS in a photo with his Dad check out what he said about his Dad

The nollywood star Femi Adebayo and his biological ..

According to him making sweet captions on his Instagram post saying ” I have so many people who call me to mentor them but I salute the man whom am proud to call my mentor as my mentor pls help me to salute him

Election jubilation Victory of pmb turns violence in taraba

As Jalingo citizens celebrate the victory of their party on the street chanting the songs of Victory some hoodlums turn this to some thing else by falling billboards of other parties and burning them at early hours of Wednesday.

The entrance of government house were not speared as they move round the capital of jalingo ..in taraba.

The security see this as a way of breaking down of laws which compelled the state security to intervene as the crowd was brought under control by the security agent.

The spoke person of State command David misail said All hands are on desk to ensure that all security agent carry out their lawful duties.

Buhari To Receive certificate of return by 2pm to pm

The president elect Muhammadu buhari will get his certificate by 2pm today been 27 February 2019

This was disposition by the inec chairman Prof Mahmood after the coalition of the final result of the presidential votes declaring the All the progressive party candidate muhammdu buhari which is emerge as the winner in the early hours of Wednesday following the rules of law which said a winner should be giving the certificate 7 days when he is declared as the winner …more details on the way.

Rivers APC ex-official, Fubara, was tied like crocodile, beheaded – Party agent


Rivers State party agent for All Progressives Congress, APC, in Saturday’s presidential election, Samson Igerebara, yesterday, gave a graphic description of how militants killed, tied up, beheaded and paraded the community with the head of the party’s ex-official, Ignatius Fubara, shortly before Saturday’s election.
APC
APC wins Senate seat in Gombe South
Igerebara also narated how Mowan Exeter, his elder

Speaking at the state Collation Centre in Port Harcourt, Igerebara said there was no way the number of recorded voters could have voted during the ensuing stampede.
The Independent National Electoral Commission, INEC, had announced 72,330 votes for Peoples Democratic Party, PDP, and 72,766 votes for APC in the presidential polls held in Andoni Local Government Area, same day they were killed.
According to him, “he was killed alongside his elder brother and nephew. Thereafter, Mowan’s corpse was dragged round the streets of Asarama.
“At that point, everybody in the community ran away. From 8a.m. till 5p.m., you could hardly see even a fowl on the street.
“It is unimaginable for anybody to say elections took place in that Azarama Ward 9. Again, in Ward 8, precisely, Ajaghaja, Rivers APC Ex-Official, Ignatius Fubara, was tied as you would tie a crocodile.
“He was then taken to a slab where his head was chopped off. And those who chopped off his head demonstrated round the community with it.
“It is clear that a sane person would not stay in such environment to conduct elections, yet the Collation Officer and the Electoral Officer turned in results.
“For a human being to turn in results on the blood of innocent souls is the height of injustice and the authorities must look into it.”

Buhari vs Atiku: Results of 29 LGAs in Kano emerge

The News Agency of Nigeria (NAN) reports that Electoral Officers for Kunchi, Rimin Gado, Bagwai, Gabasawa, Bunkure and Karaye Local Government Areas made the announcements while presenting their results to the Independent National Electoral Commission (INEC) in Kano.

Announcing the results for Kunchi Local Government area, Prof. Saminu Iliyasu, Electoral Officer for the Presidential Election in the area, said APC presidential candidate polled 20,375 to beat PDP candidate, who scored 4,983 votes.

Similarly, the Electoral Officer for Rimi Gado LGA, Dr Ibrahim Surajo, announced that Buhari scored 20,589 votes to beat Abubakar, who polled 10,305 votes.

Prof. Isa Abdulsamad, Electoral Officer, Bagwai Local Government Area, said APC scored 23,375 votes to defeat PDP, which scored got 10,584 votes.

In Gabasawa Local Government Area, the Electoral Officer, Prof. Mustapha Mukhtar, said Buhari got 24,420 votes to beat Abuabakar, who polled 6,130 votes.

The former National Security Adviser was reported dead..read details..

  • Former national security adviser of ex-president Goodluck Jonathan, Sambo Dasuki (R), speaks with his lawyer Ahmed Raji, during his trial at the federal high court in Abuja, on September 1, 2015. Nigerian prosecutors on September 1, 2015 slapped a charge of unlawful possession of arms against Dasuki. Dasuki was arraigned on a “one-count charge of being in possession of firearms without licence,” Prosecutor Mohammed Diri told the federal high court in Abuja. AFP PHOTO DSS, Dasuki’s family debunks news of Ex-NSA’s death

  • ON February 23, 2019 4:09 PM / IN News /

  • Comments

  • The Department of State Security (DSS) has refuted the news making the rounds that former National Security Adviser (NSA), Colonel Sambo Dasuki, has died at their detention facility.

  • The news of Dasuki death had flooded various social media platforms on the election’s day in Nigeria.

  • The DSS spokesperson, Peter Afunanya while reacting to the news of Dasuki’s death, said the immediate past NSA is not only alive, but in good mental and health condition.

This might not look good as Tinubu Aka Jagaban dumps pmb request…..

The All progressive change (APC)

National leader Chief Tinubu Ahmed A k a Jagaban refuse to grant the request of president muhammadu buhari for him to lead campaign ahead of the election.

Despite his refusal he is still putting more effort to let the party stand firm and never loose focus.. according to him..this refusal is to enable him to focus on the south region campaign.

Taiwan Becomes First Asian Country to Unveil Draft Law on Same-sex Marriages

The law would give same-sex couples similar legal protections for marriage as heterosexuals, but marriage in civil law would remain defined as between a man and woman.
Taipei: Taiwan on Thursday proposed a draft law to allow same-sex marriage in Asia’s first such bill, but the legislation was criticised by rights activists and conservative groups amid a heated debate over marriage equality.
Voters opposed marriage equality in a series of referendums late last year, defining marriage as between a man and a woman and asking for a special law to be enacted for same-sex union
The draft law unveiled by cabinet on Thursday would give same-sex couples similar legal protections for marriage as heterosexuals, but marriage in civil law would remain defined as between a man and woman.
Premier Su Tseng-chang said the bill respected the referendum results, although activists had said a separate law for gay marriage was discriminatories

“Controversies are expected about the proposal, but I really hope our homosexual friends can wait a bit longer,” Su said in a statement. “This might fall short of expectations, but after all it’s a start,” he said.

Jennifer Lu, coordinator of Marriage Equality Coalition Taiwan, said the draft did not give complete legal protections to same-sex couples. She acknowledged the pressure on the government from all sides, but said activists will continue to fight for equal rights.

Taiwan’s parliament is expected to vote on the draft bill by late May, a deadline for legislation set by the constitutional court in May 2017 when it ruled that same-sex couples had the right to legally marry.

The divisive issue has been a challenge for President Tsai Ing-wen, whose party suffered a major defeat in local elections in November amid criticism over her reform agenda, including marriage equality.

Conservative groups that opposed same-sex marriage during the referendum said they will fight the draft bill too. The Coalition for the Happiness of Our Next Generation on Thursday called the draft “unacceptable”.

Please guys we are getting old we need husband if you are interested here is our numbers..08156….

Women in military are like ordinary women too, they have blood flowing through their veins and have needs which they long to see satiated. They go through many ordeals like ordinary people and are susceptible to pains too; they however, handle their pain better than most people out there would. Most men believe it is going out of bounds when you approach a military woman for advanced friendship.

They blow things out of proportion by thinking these women could beat them up any time or set them up peradventure they misbehave, it should however be noted, that dating a woman in the military is the same as dating any other woman. What depicts how far that friendship would go is the manner of approach and the ability to present oneself with an aura of dignity and gentility.

Below are some of the things you don’t know about women in the military.

Emotional

They Embrace Motherhood

While so many people share an unreal belief about military women being wrecks when it comes to marital bliss, some of them are married and they embrace motherhood with a shocking interest. They are after all normal and have all it takes to raise a family. They put everything they have into use to ensure their children live normal lives. They could be stern and instill discipline in their wards at tender ages. They are regular moms who strive hard to perform their motherly obligations.

Supportive

Most people believe military women are mean and therefore avoid them. They could be excellent friends when people get to know them more. Same way they could be tough and intimidating, they could also be fierce when it comes to fighting for their friends and loved ones.

Responsibilities

It is misconstrued when people think military women’s problems have been completely solved due to the financial security that comes with their appointment. Nevertheless, they have stacks of responsibilities that go beyond sorting with money. They get weighed down by the thoughts of the risks of their jobs, instability often brought by deployment, affairs that concern their children and spouses. With all these, they tend to vent and exhale; like everyone else. But people get sentimental and believe they are naturally aggressive.

Sexual Favors

Not every woman in the military sleeps around. Many people believe most women in the military are loose and have traded sexual favors for work favors. It is the general perception that there is a major somewhere rocking their boats. Some women in military have dignity and have been able to maintain healthy non-sexual relationships with their superiors thereby maintaining stability in their career.

Enduring Scrutiny

Unknown to the general public, women in military also fight different battles in their chosen profession. The military is still dominated by testosterone while the women struggle to fit in. Failure is always expected when they are given tasks as a result of gender discrimination. It is disheartening for them to know the public also scrutinize them by seeing them as a different entity.

Attacking The Mole

Women in military have had their fair share of failures in marriages just like the successes have been discussed. The fundamental problem has still not been addressed. Seeing the women in uniform is a turn on for some men. They appreciate their bravery and get infatuated. At the long run, broken homes and relationships aren’t inevitable. The whole blame is mostly put on the women oblivious to the fact that the military indoctrination didn’t break the relationship. Are men ready to give up their job security and pack up when the women get deployed?

BREAKING] Elections: FG declares Friday public holiday, excludes bankers

In preparation for the February 23 presidential and national assembly elections, the Federal Government has declared Friday, February 22, 2019, as a public holiday,

The Ministry of Interior in a statement, on Wednesday, said bankers and those offering essential services across the nation are excluded in observing the public holiday.

“The Federal Government declares Friday, February 22, 2019 as work-free day. Those providing essential duties and bankers are excluded.

In preparation for the February 23 presidential and national assembly elections, the Federal Government has declared Friday, February 22, 2019, as a public holiday,

The Ministry of Interior in a statement, on Wednesday, said bankers and those offering essential services across the nation are excluded in observing the public holiday.

  • “The Federal Government declares Friday, February 22, 2019 as work-free day. Those providing essential duties and bankers are excluded.

Jamiublog.com.ng

Curriculum and Its different definations

Types of curriculum with their definitions
©Leslie Owen Wilson. Ed. D. Contact Leslie
What are the different definitions and types of curriculum?
When I asked my students what curriculum means to them, they always indicated that it means the overt or written curriculum – thinking of a curriculum manual with goals and objectives, or their textbooks. However, the word “curriculum” as it is defined from its early Latin origins means literally “to run a course.” If one thinks of a marathon with mile and direction markers, signposts, water stations, and officials and coaches along the route, this beginning definition is a metaphor for what the curriculum has become in the education of our children.
Here are multiple definitions of curriculum, from Oliva (1997) (4)
Curriculum is:
That which is taught in schools
A set of subjects.
Content
A program of studies.
A set of materials
A sequence of courses.
A set of performance objectives
A course of study
Is everything that goes on within the school, including extra-class activities, guidance, and interpersonal relationships.
Everything that is planned by school personnel.
A series of experiences undergone by learners in a school.
That which an individual learner experiences as a result of schooling. p 4
What are the different kinds of curriculum?
Obviously the answer to this question is subject to interpretation. Since curriculum reflects the models of instructional delivery chosen and used, some might indicate that curriculum could be categorized according to the common psychological classifications of the four families of learning theories “ Social, Information Processing, Personalist, and Behavioral.”
Longstreet and Shane have dubbed divisions in curricular orientations as: child-centered, society-centered, knowledge-centered, or eclectic . Common philosophical orientations of curriculum parallel those beliefs espoused by different philosophical orientations – Idealism, Realism, Perennialism, Essentialism, Experimentalism, Existentialism, Constructivism, Reconstructivism and the like.
Whatever classification one gravitates to, the fact remains that at one time or another curriculum in the United States has, at some level, been impacted by all of the above. In essence, American curriculum is hard to pin down because it is multi-layered and highly eclectic.
My personal definition (Wilson, 1990) of curriculum is:
Anything and everything that teaches a lesson, planned or otherwise. Humans are born learning, thus the learned curriculum actually encompasses a combination of all of the following — the hidden, null, written, political and societal etc.. Since students learn all the time through exposure and modeled behaviors, this means that they learn important social and emotional lessons from everyone who inhabits a school — from the janitorial staff, the secretary, the cafeteria workers, their peers, as well as from the deportment, conduct and attitudes expressed and modeled by their teachers. Many educators are unaware of the strong lessons imparted to youth by these everyday contacts.”
The following represent the many different types of curricula used in schools today
Type of Curriculum Definition
1. Overt, explicit, or written curriculum Is simply that which is written as part of formal instruction of schooling experiences. It may refer to a curriculum document, texts, films, and supportive teaching materials that are overtly chosen to support the intentional instructional agenda of a school. Thus, the overt curriculum is usually confined to those written understandings and directions formally designated and reviewed by administrators, curriculum directors and teachers, often collectively.
2. Societal curriculum (or social curricula) As defined by Cortes (1981). Cortes defines this curriculum as:…[the] massive, ongoing, informal curriculum of family, peer groups, neighborhoods, churches, organizations, occupations, mass media, and other socializing forces that “educate” all of us throughout our lives. 24
This type of curricula can now be expanded to include the powerful effects of social media (YouTube; Facebook; Twitter; Pinterest, etc) and how it actively helps create new perspectives, and can help shape both individual and public opinion.
3. The hidden or covert curriculum That which is implied by the very structure and nature of schools, much of what revolves around daily or established routines.
Longstreet and Shane (1993) offer a commonly accepted definition for this term – the “hidden curriculum,” which refers to the kinds of learnings children derive from the very nature and organizational design of the public school, as well as from the behaviors and attitudes of teachers and administrators…. ” 46
Examples of the hidden curriculum might include the messages and lessons derived from the mere organization of schools — the emphasis on: sequential room arrangements; the cellular, timed segments of formal instruction; an annual schedule that is still arranged to accommodate an agrarian age; disciplined messages where concentration equates to student behaviors were they are sitting up straight and are continually quiet; students getting in and standing in line silently; students quietly raising their hands to be called on; the endless competition for grades, and so on. The hidden curriculum may include both positive or negative messages, depending on the models provided and the perspectives of the learner or the observer.
In what I term floating quotes, popularized quotes that have no direct, cited sources, David P. Gardner is reported to have said: We learn simply by the exposure of living. Much that passes for education is not education at all but ritual. The fact is that we are being educated when we know it least.
4. The null curriculum That which we do not teach, thus giving students the message that these elements are not important in their educational experiences or in our society. Eisner offers some major points as he concludes his discussion of the null curriculum. The major point I have been trying to make thus far is that schools have consequences not only by virtue of what they do teach, but also by virtue of what they neglect to teach. What students cannot consider, what they don’t processes they are unable to use, have consequences for the kinds of lives they lead. 103
Eisner (1985, 1994) first described and defined aspects of this curriculum. He states: There is something of a paradox involved in writing about a curriculum that does not exist. Yet, if we are concerned with the consequences of school programs and the role of curriculum in shaping those consequences, then it seems to me that we are well advised to consider not only the explicit and implicit curricula of schools but also what schools do not teach. It is my thesis that what schools do not teach may be as important as what they do teach. I argue this position because ignorance is not simply a neutral void; it has important effects on the kinds of options one is able to consider, the alternatives that one can examine, and the perspectives from which one can view a situation or problems. …97
From Eisner’s perspective the null curriculum is simply that which is not taught in schools. Somehow, somewhere, some people are empowered to make conscious decisions as to what is to be included and what is to be excluded from the overt (written) curriculum. Since it is physically impossible to teach everything in schools, many topics and subject areas must be intentionally excluded from the written curriculum. But Eisner’s position on the “null curriculum” is that when certain subjects or topics are left out of the overt curriculum, school personnel are sending messages to students that certain content and processes are not important enough to study. Unfortunately, without some level of awareness that there is also a well-defined implicit agenda in schools, school personnel send this same type of message via the hidden curriculum. These are important to consider when making choices. We teach about wars but not peace, we teach about certain select cultures and histories but not about others. Both our choices and our omissions send messages to students.
5. Phantom curriculum The messages prevalent in and through exposure to any type of media. These components and messages play a major part in the enculturation of students into the predominant meta-culture, or in acculturating students into narrower or generational subcultures.
6. Concomitant curriculum What is taught, or emphasized at home, or those experiences that are part of a family’s experiences, or related experiences sanctioned by the family. (This type of curriculum may be received at church, in the context of religious expression, lessons on values, ethics or morals, molded behaviors, or social experiences based on the family’s preferences.)
7. Rhetorical curriculum Elements from the rhetorical curriculum are comprised from ideas offered by policymakers, school officials, administrators, or politicians. This curriculum may also come from those professionals involved in concept formation and content changes; or from those educational initiatives resulting from decisions based on national and state reports, public speeches, or from texts critiquing outdated educational practices. The rhetorical curriculum may also come from the publicized works offering updates in pedagogical knowledge.
8. Curriculum-in-use The formal curriculum (written or overt) comprises those things in textbooks, and content and concepts in the district curriculum guides. However, those “formal” elements are frequently not taught. The curriculum-in-use is the actual curriculum that is delivered and presented by each teacher.
9. Received curriculum Those things that students actually take out of classrooms; those concepts and content that are truly learned and remembered.
10. The internal curriculum Processes, content, knowledge combined with the experiences and realities of the learner to create new knowledge. While educators should be aware of this curriculum, they have little control over the internal curriculum since it is unique to each student. Educators can explore this curricula by using instructional assessments like “exit slips,” reflective exercises, or debriefing discussions to see what students really remember from a lesson. It is often very enlightening and surprising to find out what has meaning for learners and what does not.
11. The electronic curriculum Those lessons learned through searching the Internet for information, or through using e-forms of communication. (Wilson, 2004) This type of curriculum may be either formal or informal, and inherent lessons may be overt or covert, good or bad, correct or incorrect depending on ones’ views. Students who use the Internet on a regular basis, both for recreational purposes (as in blogs, wikis, chatrooms, listserves, through instant messenger, on-line conversations, or through personal e-mails and sites like Twitter, Facebook, or Youtube) and for personal online research and information gathering are bombarded with all types of media and messages. Much of this information may be factually correct, informative, or even entertaining or inspirational. But there is also a great deal of other e-information that may be very incorrect, dated, passé, biased, perverse, or even manipulative.
The implications of the electronic curriculum for educational practices are that part of the overt curriculum needs to include lessons on how to be wise consumers of information, how to critically appraise the accuracy and correctness of e-information, as well as how to determine the reliability of electronic sources. A lso, students need to learn how to be artfully discerning about the usefulness and appropriateness of certain types of information. Like other forms of social interaction, students need to know that there are inherent lessons to be learned about appropriate and acceptable “ netiquette” and online behaviors, to include the differences between “fair and legal usage,” vs. plagiarism and information piracy.
If you would like to use either my PDF of
different curricular types or my 10Netiquette in PDF format, please read the usage post before downloading.
References:
Cortes, C.E. (1981) The societal curriculum: Implications for multiethnic educations. In Banks, J.A (ed.) Educations in the 80’s: Multiethnic education. National Education Association.
Eisner, E.W. (1994) T he educational imagination: On design and evaluation of school programs. (3rd. ed) New York: Macmillan.
Longstreet, W.S. and Shane, H.G. (1993) Curriculum for a new millennium. Boston: Allyn and Bacon.
Oliva, P. (1997) The curriculum: Theoretical dimensions . New York: Longman.
Wilson, L. O. (1990, 2004, 2006) Curriculum course packets ED 721 & 726, unpublished
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10 reasons why most youth are still stuck in poverty..1 is..

1 ..most youth consider every morning as the best for calling girlfriend, chatting on social medias wasting their best time that’s useful for the best for nothing

While not realizing that every morning should serve as a curriculum of your live achievement ..time to think of what’s best for you and that which is not best ..

2. Most youth blame their past for their misfortune ..not realizing that most people seen as successful ones today if u trace back from their predecessors it not about their inheritance but for their hardworking ..you have to let your past serve as your motivation not a blame ..if your father is poor that doesn’t make you poor too ..you can also make a difference so consider this.

3. Most youth today depend on government policy ..there is saying when a policy favor some individual it becomes law but when it didn’t it becomes an issue ..no, bad government does not make you financially handicap when you realize your potential and do something positive with this potentiality…to be continued…

REPRODUCTION IN ALGAE

Reproduction in Algae: 3 Modes
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The following points highlight the three modes of reproduction in algae. The modes are: 1. Vegetative 2. Asexual 3. Sexual.
Mode # 1. Vegetative Reproduction:
In this type, any vegetative part of the thallus develops into new individual. It does not involve any spore formation and there is no alternation of generations. It is the most common method of reproduction in algae.
The vegetative reproduction in algae is of the following types:

a. Cell division or fission:
It is the simplest method of reproduction. The unicellular forms of algae commonly reproduce by this simple process, often called binary fission as found in Chlamydomonas, Synechococcus (Fig. 3.16A), diatoms etc. In this method the vegetative cell divides mitotically into two daughter cells, those finally behave as new indi­vidual.
b. Fragmentation:
In this method, the multicellular filamentous thallus breaks into many-celled fragments, each of which gives rise to a new individual. The fragmentation may be accidental or by the formation of separation discs or by some other mechanical force or injury. It is found in Spirogyra, Ulothrix, Oedo- gonium, Zygnema, Cylindospermum (Fig. 3.16B) etc.
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c. Hormogonia:
This method of vegetative reproduction is found in blue-green algae. The trichomes of blue-green algae break up within the sheath into many-celled segments called hormogo­nia or hormogones. They remain delimited by the formation of heterocysts, separation discs or necridia or by the death and decay of intercalary cells of the trichome. Hormogonia are commonly found in Nostoc, Oscillatoria, Cylindosporium etc.
d. Formation of Adventitious Branches:
Adventitious branches are formed in different large thalloid algae, which, when detached from the plant body, develop into new individuals (e.g., Fucus, Dictyota). Protonema-like adventitious branches are formed from the internodes of Chara, stolons of Cladophora glomareta etc.
e. Bulbils:
Tuber-like outgrowths are developed due to storage of food at the tip of rhizoids and on the lower nodes of Chara, called bulbils (Fig. 3.16C). After detachment from the plant body, bulbils grow into new plants.

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president of the federation has critically warn that for what so ever will anyone cause trouble or sabotage the election that is on forth coming did that at the expense of his own life .

Speaking at the conference yesterday with the stakeholders that he had declare the state of emergency to deal decisefully with anyone who will sabotage the election..he further said that every Nigeria who is willing to vote should be respected to do so and to choose any leader they want… according to him “I am not afraid because I have many supporters across the 36 state ..so I have no reason to fear because I have been through this before..this statement was made by the president at end of his speech.

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The following points highlight the three modes of reproduction in algae. The modes are: 1. Vegetative 2. Asexual 3. Sexual.
Mode # 1. Vegetative Reproduction:
In this type, any vegetative part of the thallus develops into new individual. It does not involve any spore formation and there is no alternation of generations. It is the most common method of reproduction in algae.
The vegetative reproduction in algae is of the following types:
ADVERTISEMENTS:
a. Cell division or fission:
It is the simplest method of reproduction. The unicellular forms of algae commonly reproduce by this simple process, often called binary fission as found in Chlamydomonas, Synechococcus (Fig. 3.16A), diatoms etc. In this method the vegetative cell divides mitotically into two daughter cells, those finally behave as new indi­vidual.
b. Fragmentation:
In this method, the multicellular filamentous thallus breaks into many-celled fragments, each of which gives rise to a new individual. The fragmentation may be accidental or by the formation of separation discs or by some other mechanical force or injury. It is found in Spirogyra, Ulothrix, Oedo- gonium, Zygnema, Cylindospermum (Fig. 3.16B) etc.
ADVERTISEMENTS:
c. Hormogonia:
This method of vegetative reproduction is found in blue-green algae. The trichomes of blue-green algae break up within the sheath into many-celled segments called hormogo­nia or hormogones. They remain delimited by the formation of heterocysts, separation discs or necridia or by the death and decay of intercalary cells of the trichome. Hormogonia are commonly found in Nostoc, Oscillatoria, Cylindosporium etc.
d. Formation of Adventitious Branches:
Adventitious branches are formed in different large thalloid algae, which, when detached from the plant body, develop into new individuals (e.g., Fucus, Dictyota). Protonema-like adventitious branches are formed from the internodes of Chara, stolons of Cladophora glomareta etc.
e. Bulbils:
Tuber-like outgrowths are developed due to storage of food at the tip of rhizoids and on the lower nodes of Chara, called bulbils (Fig. 3.16C). After detachment from the plant body, bulbils grow into new plant

The following points highlight the three modes of reproduction in algae. The modes are: 1. Vegetative 2. Asexual 3. Sexual.
Mode # 1. Vegetative Reproduction:
In this type, any vegetative part of the thallus develops into new individual. It does not involve any spore formation and there is no alternation of generations. It is the most common method of reproduction in algae.
The vegetative reproduction in algae is of the following types:
ADVERTISEMENTS:
a. Cell division or fission:
It is the simplest method of reproduction. The unicellular forms of algae commonly reproduce by this simple process, often called binary fission as found in Chlamydomonas, Synechococcus (Fig. 3.16A), diatoms etc. In this method the vegetative cell divides mitotically into two daughter cells, those finally behave as new indi­vidual.
b. Fragmentation:
In this method, the multicellular filamentous thallus breaks into many-celled fragments, each of which gives rise to a new individual. The fragmentation may be accidental or by the formation of separation discs or by some other mechanical force or injury. It is found in Spirogyra, Ulothrix, Oedo- gonium, Zygnema, Cylindospermum (Fig. 3.16B) etc.
ADVERTISEMENTS:
c. Hormogonia:
This method of vegetative reproduction is found in blue-green algae. The trichomes of blue-green algae break up within the sheath into many-celled segments called hormogo­nia or hormogones. They remain delimited by the formation of heterocysts, separation discs or necridia or by the death and decay of intercalary cells of the trichome. Hormogonia are commonly found in Nostoc, Oscillatoria, Cylindosporium etc.
d. Formation of Adventitious Branches:
Adventitious branches are formed in different large thalloid algae, which, when detached from the plant body, develop into new individuals (e.g., Fucus, Dictyota). Protonema-like adventitious branches are formed from the internodes of Chara, stolons of Cladophora glomareta etc.
e. Bulbils:
Tuber-like outgrowths are developed due to storage of food at the tip of rhizoids and on the lower nodes of Chara, called bulbils (Fig. 3.16C). After detachment from the plant body, bulbils grow into new plant