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?

TLS Online TPP Program

#Question id: 12200

#Unit 6. System Physiology – Plant

Given some observation of the auxin signalling pathway, which one of the following are the incorrect prediction about signalling?

TLS Online TPP Program

#Question id: 12201

#Unit 6. System Physiology – Plant

ARF dependent signalling are regulated by auxin concenteration, given some condition followed;

I) In the absence of auxin

 II) In the presence of auxin

Find the statements that are correctly matched with given certain condition,

a)  AUX/IAA repressor proteins containing interaction domains similar to those found in the ARFs form heterodimers with the ARFs and thus repress transcriptional activation

b)  AUX/IAA repressors are recruited to the TIR1/AFB receptor complex and are tagged with ubiquitin for degradation by the 26S proteasome

c) ARFs form homodimers via conserved interaction domains and recruit chromatin remodelling

Which of the following combination is correct?

TLS Online TPP Program

#Question id: 12202

#Unit 6. System Physiology – Plant

Auxin-responsive genes typically have

TLS Online TPP Program

#Question id: 12203

#Unit 6. System Physiology – Plant

Which factor function as auxin co-receptors, with auxin acting as a “molecular glue”?

TLS Online TPP Program

#Question id: 12204

#Unit 6. System Physiology – Plant

Feedback regulation represents another key mechanism employed to attenuate a response such as

a) AUX/IAA proteins can bind to the promoters of their own genes and repress their own expression

b) auxin signaling triggers the degradation of AUX/IAA repressors, the ensuing transcription of auxin response genes leads to the replacement of AUX/IAA proteins and thus to response attenuation or termination

c) AUX/IAA genes, which encode the AUX/IAA auxin repressor proteins, have auxin response element binding sites located in their promoter regions

During the feedback regulation mechanism of auxin several responses are trigger, find out the correct sequences of these responses.

TLS Online TPP Program

#Question id: 12205

#Unit 7. System Physiology – Animal

Before the preovulatory surge in luteinizing hormone, granulosa cells of the follicle secrete which of the following?