(a) Where do the signals for parturition originate from in humans?
(b) Why is it important to feed the newborn babies on colostrums?(a) The signals for parturition originate from the fully developed fetus and the placenta which induce mild uterine contractions called foetal ejection reflex. This triggers release of oxytocin (birth hormone) from the maternal pituitary gland.
(b) The yellowish fluid colostrum secreted by mother during the initial days of lactation has abundant antibodies (IgA) that protects the infant or new born babies and develops resistance in them.
Given reasons for the following:
(a) The human testes are located outside the abdominal cavity.
(b) Some organisms like honey-bees are called parthenogenetic animals.
Name the respective pattern of inheritance where F1 phenotype
(a) does not resemble either of the two parents and is in between the two.
(b) resembles only one of the two parents.
How is the entry of only one sperm and not many ensured into an ovum during fertilisation in humans?
Write the name of the following:
(a) The most common species of bees suitable for apiculture
(b) An improved breed of chicken