Growth hormone secretion is regulated by negative feedback, three feedback loops including both long and short loops are involved,

a.  GHRH inhibits its own secretion from the hypothalamus via an ultrashort-loop feedback.

b. Somatomedins, which are by-products of the growth hormone action on target tissues, inhibit secretion of growth hormone by the anterior pituitary.

c. Both growth hormone and somatomedins stimulate the secretion of somatostatin by the hypothalamus.

d. SRIF is also secreted by the hypothalmus and acts on the somatotrophs to stimulate growth hormone secretion.

Which one of the following represents all correct statements?

#Question id: 5436

#Unit 8. Inheritance Biology

Quantitative characteristics arise from two phenomena either polygenic or environmental influence on genotype. Which of the following is not character of quantitative polygenic trait?

#Question id: 5437

#Unit 8. Inheritance Biology

A pure line dominant plant has height of 100 cm while pure line of recessive plant has 20 cm. If one dominant gene contribution is 8 cm, what is number of QTL control plant height?

#Question id: 5438

#Unit 8. Inheritance Biology

Which of the following statement is incorrect?

#Question id: 5440

#Unit 8. Inheritance Biology

Human height is control by 5 pair of polygene . A pure line dominant human has height of 100 cm while pure line of recessive human has 20 cm. What will be average height of human with genotype aabbCCDDEe?

#Question id: 5441

#Unit 8. Inheritance Biology

Two pure line of corn have mean cob length of 15 cm and 5 cm, respectively. 6 polygenes involved in this trait exhibit additive gene action. Crossing these two lines is expected to produce a progeny population with mean cob length of

#Question id: 5443

#Unit 8. Inheritance Biology

Two varieties of maize averaging 25 and 125 inches in height, respectively, are crossed. The F1 progeny is quite uniform averaging 75 inches in height. Plant height is control by 3 QTL, what is the probability of plant with 25 inch height in F2 generation?