Following statements regarding to the molecular processes of capacitation.

A. The sperm cell membrane is altered by the removal of cholesterol by albumin proteins in the female reproductive tract.

B. Particular proteins or carbohydrates on the sperm surface are lost during capacitation.

C. The membrane potential of the sperm cell becomes more positive as potassium ions leave the sperm. This change in membrane potential may allow calcium channels to be opened and permit calcium to enter the sperm.

D. Calcium and bicarbonate ions are critical in activating cAMP production and in facilitating the membrane fusion events of the acrosome reaction.

E. As a result of cAMP formation, protein phosphorylation occurs. Once they are phosphorylated, some proteins migrate to the surface of the sperm head. One of these proteins is juno, which is critical in sperm-egg fusion.

which one of the following combinations is correct?

#Question id: 11289

#Unit 10. Ecological Principles

Consumption efficiency (CE) is the proportion of production at one trophic level (Prodn n-1) that is eaten by, or ingested, by the next trophic level (In) but Assimilation efficiency (AE) is the proportion of ingested energy assimilated in to blood stream

Which of the following is incorrect statement?

A) In terrestrial herbivore, AE is greater than CE

B) In aquatic herbivore AE is equal to CE 

C) CE of grass land herbivore is often greater than forest herbivore

D) AE of herbivore is often greater than carnivore

#Question id: 11290

#Unit 10. Ecological Principles

Which of the following statement are incorrect?

#Question id: 11291

#Unit 10. Ecological Principles

A small lake has three trophic levels- phytoplankton (autotrophs), Zooplankton (herbivore) and planktivorous fish (primary carnivore). In this lake, addition of nutrients is allowed to study the 'bottom up' effects". What is the expected biomass of phytoplankton and zooplankton tropic levels?

#Question id: 11292

#Unit 10. Ecological Principles

In an pond ecosystem the _____ is always greater than the _____ .

(a) number of primary producers . . . number of secondary consumers

(b) biomass of secondary consumers . . . biomass of primary consumer

(c) assimilation efficiency of primary consumers . . . assimilation efficiency of secondary consumers

(d) biomass of primary producers . . . biomass of primary consumers

#Question id: 11293

#Unit 10. Ecological Principles

Measurement of phytoplankton production, take sample of phytoplankton suspended in two bottles in lake. One bottle (D) is dark in colour but second bottle (L) light in colour. After some time productivity measure as follow Where Lo –oxygen concentration in light bottle, Do –oxygen concentration in Dark bottle, Io –oxygen concentration in bottle before incubation    

A)  Lo- Do                     B) Lo- Io  C) Io- Do

#Question id: 11294

#Unit 10. Ecological Principles

A small lake has three trophic level – Phytoplankton(autotroph) , Zooplankton (herbivore ) and planktivorous fish ( primary carnivore) . In to this lake Population of some other primary carnivore introduced to study top down effect . What is expected long term consequence of this  introduction ?