Answer:
The options are
A.Independent assortment
B. Mutation
C. Crossing over
D. Non disjunction
The answer is A.Independent assortment
Explanation:
Independent assortment of genes involves the separation of genes during the formation and development of reproductive cells.
A boy has XY chromosome and a lady has XX chromosomes. This explains why Sue inherited the mother's copy of chromosome 13 but their father's copy of chromosome 14 while her brother Billy inherited their father's copy of both chromosomes 13 and 14. He inherited both due to the presence of XY chromosomes.
Answer:
C. is unstable, with a short half life
Explanation:
Paracrine hormones are the hormones that act on neighboring cells only. These hormones or chemicals are largely unstable and have a brief life as do not visit the distantly placed target cells. For instance, somatostatin is secreted by D cells of the pancreas. It acts in a paracrine manner and inhibits the discharge of hormones from the neighboring beta and alpha cell.
Likewise, one of the functions of unstable NO gas is to serve as a vasodilator. It is released by epithelium cells and serves to dilate arterioles and relax precapillary sphincters. Then it is degraded.
Answer:
c. A bacterial cell that lacked receptors on its surface for that antibiotic
Explanation:
If the bacteria lacks the receptors on its surface meant for that antibiotic then it will be best defense for the survival of that bacteria. It is receptors which interact with the antibiotic so as to permit it inside the cell. Therefore, in the absence of receptors, it doesn't matter how much antibiotic is lying in the external environment of that bacteria, the antibiotic will not be able to enter the bacterial cell to kill it. Hence, the bacteria will be able to survive easily.
Answer:
the answer is carbohydrate
Answer:by being produced in the testes outside the body
Explanation: spermatogenesis is the production of male gamates,the sperm.this process occurs in the seminiferous tubules in the testes.epithelial cells produces the primary spermatocyte which divides to give a secondary spermatocyte.
The secondary spermatocyte divides to form spermatids,which differentiates to form the spermatozoons.
Testis is housed in the scrotal sac.
Sperm production is sensitive to temperature. Too high temperature can cause formation of abnormal cells . As a result the scrotal sac is located outside the body
