Which one of the following is NOT secreted by capillary endothelium?

• Prostacyclin

• Guanosine

• Endothelin

• Nitric oxide

The "Mayer waves" in the blood pressure orginate due to:

• systole and diastole of ventricle

• inspiration and expiration

• reflex oscilliation of neural pressure control mechanisms

• Bainbridge reflex

133.

The maturation of red blood cells does not depend on:

• folic acid

• vitamin B₁₂

• pyridoxine

• tocopherol

Which one of the following is NOT a function of angiotenism II?

• Facilitates the release of norepinephrine from post-ganglionic sympathetic neurons.

• Increases the sensitivity of baroreflex by acting on brain

• Produces arteriolar contraction

• Increases the secretion of vasopressin

The pedigree below represents the inheritance of an autosomal recessive trait.

What is the probability that individual '6' is heterozygote?

• 1/4

• 1/2

• 2/3

• 1/3

A population grows according to the logistic growth equation, $\frac{\mathrm{dN}}{\mathrm{dt}}=\mathrm{rN}\left(1-\frac{\mathrm{N}}{\mathrm{K}}\right)$, where $\frac{\mathrm{dN}}{\mathrm{dt}}$ is the rate of population growth, τ is the intrinsic rate increase. N is population size and k is the carrying capacity of the environment. According to this equation population growth rate is maximum at 

• K/4

• K/2

• K

• 2K

The allel l in Drosophila is recessive, sexlinked and lethal when homozygous or hemizygous. If a female of the genotype Ll is crossed with a male, what is the ratio of females: males in the progeny? 

Deamination of bases is a common chemical event that produces spontaneous mutation. Which one of the following bases will be formed by deamination of 5-methylcytosine? 

• Uracil

• Thymine

• Cytosine

• Guanine

In a population of 2000 individuals of a plant species, genetic difference at a single locus leads to different flowers colours. The alleles are incompletely dominant. The population has 100 individuals with the genotype rr ( white flowers), 800 individuals with the genotype Rr (pink flowers) and the remaining have genotype RR( red flowers). What is the frequency of the r allele in the population?

• 0.25

• 0.50

• 0.75

• 1.00

Which of the following plastid coding region(s) have been recommended as a core barcode by Plant Working Group of the consortium for the Barcode of Life?

• CO1 and rbcL

• rbcL and matK

• CO1 and matK

• rbcL only