Given below are some behaviors strategies.

A) Fixed action pattern, complex sequence of behavior, Once released and continuous to completion, even when there is change in surrounding environment

B)  natural selection select that territorial behavior that is benefit is greater than cost 

C) Imprinting, a form of learning in which a very young animal fixes its attention on the first object with which it has visual, auditory, or tactile experience

D) Donor benefits at a cost to the recipient, the behavior is altruistic; when the recipient benefits at a cost to the donor, the behavior is selfish.

Which one of the following correct combination of true and false?

#Question id: 5562

#Unit 5. Developmental Biology

In an egg cell treated with a chemical that binds calcium and magnesium ions, the ________.

#Question id: 5563

#Unit 5. Developmental Biology

In mammalian eggs, the receptors for sperm are found in the ________.

#Question id: 5564

#Unit 5. Developmental Biology

At the moment of sperm penetration, human eggs ________.

#Question id: 5568

#Unit 5. Developmental Biology

Asexual reproduction results in offspring that are genetically identical to their parent. What type of cell process occurs to generate this type of offspring?

#Question id: 5686

#Unit 5. Developmental Biology

Following statements are regarding to double fertilization in angiosperms.

A. One sperm cell fuses with the egg cell to produce the zygote that will develop into the new embryonic plant.

B. The second sperm cell fuses with the usually binucleate central cell, giving rise to the

endosperm, the tissue that nourishes the developing embryo. This second event is not “true” fertilization in the sense of male and female gametes undergoing fusion.

C. The second sperm cell fuses with the usually binucleate central cell, giving rise to the

endosperm, the tissue that nourishes the developing embryo. This second event is “true” fertilization in the sense of male and female gametes undergoing fusion.

D. During fertilization in angiosperm, when the sperm cells are released, the egg undergoes a flux of Ca2+. Then, chemicals released from the egg appear to make the sperm competent for cell fusion.

Which of the following statements are true?

#Question id: 5685

#Unit 5. Developmental Biology

Human sperm are allowed to fertilize ova having non- functional ovastacin. The following possibilities may be of significance in the fusion of these gametes:

A.        The sperms will not fertilize ova.

B.        The sperms will bind and penetrate the zona pellucida but will not be able to fuse with ovum membrane.

C.        ZP2 will not be clipped by cortical granule protease.

D.        CD9 protein of egg membrane microvilli will not be able to interact sperm membrane proteins in the absence of ovastacin.

E.         Polyspermy may occur frequently.

Which combination of statements represent the outcome of the above event?