Tag: the life cycle of animals

Questions Related to the life cycle of animals

Animals having both the sexes in one body are called __________.

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Nematods

  2. Hermaphrodite

  3. Parasite

  4. Pseudocoelomate

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Correct Option: B
Explanation:

Certain animals like earthworm have both the sexes i.e., male and female reproductive system in one body itself. Such organisms are called as hermaphrodite. They tend to reproduce sexual by copulating.

HeLa cells used in cell biology are 

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Cancerous cells grown in cancer research laboratory

  2. Cervical cancer cell derivatives

  3. Both (A) and (B)

  4. None of the above

Show answer
Correct Option: C
Explanation:

HeLa cells, are cancerous cells  belonging to a cultured strain isolated from a patient suffering from cervical cancer. The designation HeLa is derived from the name of the patient, Henrietta Lacks. This cell line has been extensively used in cell biology research like cancers, effect of various carcinogens and xenobiotics on human cells etc. 

So.option C is correct.

Which animal exhibits sexual dimorphism ______________.

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Lobosa

  2. Ciliata

  3. Sporozoans

  4. Radiolarians

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Correct Option: A

The type of blastula formed in birds is 

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Teloblastula

  2. Holoblastula

  3. Coeloblastula

  4. Discoblastula

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Correct Option: D
Explanation:

Discoblastula is disc shaped blastula which is formed by meroblastic discoidal cleavage as in fishes, reptiles, birds and egg laying mammals.

Which of the following cells are present in mammalian testes and help to nourish sperms 

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Leydig cells

  2. Oxyntic cells

  3. Interstitial cells

  4. Sertoli cells

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Correct Option: D
Explanation:

Sertoli cells are non-gametic cells in the seminiferous tubules which provide nourishment for developing sperms.

Assertion : There is generally monospermy in most of animals.

Reason : Vitelline membrane of ovum checks polyspermy.

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Both Assertion and Reason are true and Reason is a correct explanation of Assertion

  2. Both Assertion and Reason are true but Reason is not a correct explanation of Assertion

  3. Assertion is true but Reason is false

  4. Both Assertion and Reason are false

  5. Assertion is false but reason is true.

Show answer
Correct Option: B
Explanation:

Entrance of a single sperm into an oocytes called monospermy generally monospermy is found in most of the animals. Cortical granules are extruded in the perivitelline space by exocytosis and some of these are attached along the inner surface of vitelline membrane which now thickens and becomes impervious to any other sperm entry. It is now called fertilization membrane. It prevents the polyspermy.

In most of the mammals the testes are situated outside the abdominal cavity because 

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Sperms produced in scrotal sac are more in number

  2. Sperms produced in abdominal cavity are provided with less motility

  3. Sperms produced in scrotal sac require lesser temperature for their best fertilization capacity

  4. Sperms produced in scrotal sac are bigger

Show answer
Correct Option: C
Explanation:

Testes in mammals are present out side the abdominal cavity because maturation of sperm needs low temperature. The temperature of scrotum is below (2 to 4$^{o}C$) than abdominal cavity.

Assertion : In morula stage, cells divide without increase in size.

Reason : Zona pellucida remain undivided till cleavage is complete.

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Both Assertion and Reason are true and Reason is a correct explanation of Assertion

  2. Both Assertion and Reason are true but Reason is not a correct explanation of Assertion

  3. Assertion is true but Reason is false

  4. Both Assertion and Reason are false

  5. Assertion is false but reason is true.

Show answer
Correct Option: B
Explanation:

Zygote divide vertically to form two blastomeres. This is followed by a vertical division and a horizontal division. Now, several divisions occur forming equal sized blastomeres called morula. There is no increase in size of cells. Zona pellucida is a transparent non cellular layer surrounding egg cell. It remains undivided till the cleavage is complete.

In common Turtles the females are predominant at

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Below $28^o C$

  2. Above $3^o C$

  3. Between $28^o - 33^o C$

  4. Sex is genetically determined.

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Correct Option: B

In crocodiles male sex is predominant at

biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

  1. Low temperature

  2. Intermediate temperature

  3. High temperature

  4. Ratio is genetically determined.

Show answer
Correct Option: C