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TLS Online TPP Program

#Question id: 11201

Why are action potentials usually conducted in one direction?

#Unit 7. System Physiology – Animal
  1. The nodes of Ranvier conduct potentials in one direction.
  2. The brief refractory period prevents reopening of voltage-gated sodium channels.
  3. The axon hillock has a higher membrane potential than the terminals of the axon.
  4. Voltage-gated channels for both Na+ and K+ open in only one direction.
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TLS Online TPP Program

#Question id: 12013

#Unit 10. Ecological Principles

The average daily temperature change on an exposed south-facing slope and a north-facing slope for a late summer day in the Northern Hemisphere are shown below.


The difference in the  maximum average daily  temperature between the  south-facing slope  and  the  north-facing slope is approximately
TLS Online TPP Program

#Question id: 18578

#Unit 7. System Physiology – Animal

During which stage of the general adaptation syndrome (GAS) is the risk for physiological harm, such as reduced immunity and increased susceptibility to physical or mental illness, greatest?
TLS Online TPP Program

#Question id: 10427

#Unit 6. System Physiology – Plant

HIRs require prolonged or continuous exposure to light of relatively high irradiance, these HIRs induce phytochrome responses such as
a) Synthesis of flavonoids including anthocyanins
b) Inhibition of hypocotyl elongation in various plants
c) Induction of flowering and Plumular hook opening in lettuce
d) Enlargement of cotyledons in mustard
e) Production of ethylene in sorghum
Which of the following phytochrome responses induce by HIRs is correct?
TLS Online TPP Program

#Question id: 10807

#Unit 6. System Physiology – Plant

Cyanogenic Glycosides and Glucosinolates are nitrogen containing secondary metabolites in plants. Following are some statements regarding the action of Cyanogenic Glycosides and Glucosinolates;

a) Cyanogenic Glycosides release the poison hydrogen cyanide by the action of enzyme known as Hydroxynitrile lyase

b) Release of the mustard-smelling volatiles from glucosinolates is catalyzed by a hydrolytic enzyme, called a thioglucosidase or myrosinase

c) substerate for Glycosidase is Cyanogenic glycoside and Thioglucosidase is Aglycone

d) Like cyanogenic glycosides, glucosinolates are stored in the intact plant separately from the enzymes that hydrolyze them, and they are brought into contact with these enzymes only when the plant is crushed

Which of the following combinations of above statement is true?
TLS Online TPP Program

#Question id: 2704

#Unit 2. Cellular Organization

Which of the following regions promote histone – DNA association?