Mutations are the source of all new alleles. An allele is a variant form of a gene. Variations in alleles lead to variations in organisms. Positive mutations give an organism a better chance of survival. It means that the mutation may be passed on to the offspring. Negative mutations may lead to an early death.<span> Therefore, changes in alleles from one generation to another form the basis of evolution.</span>
They digest excess or worn out organelles, food partials, and engulfed viruses or bacteria<span />
Nucleic acid is a
D. Macromolecule.
Explanation:
The ribs are a set of twelve bones which form the protective 'cage' of the thorax. They articulate with the vertebral column posteriorly, and terminate anteriorly as cartilage (known as costal cartilage). As part of the bony thorax, the ribs protect the internal thoracic organs.
Answer:
environment controlling gene expression
Explanation:
Gestational diabetes generally occurs in pregnant women. The sugar level in the bloodstream becomes little high than the normal range during pregnancy. But the glucose level returns to normal after child birth.
The pancreas secrets insulin which helps to lower the blood sugar level in the body. But during pregnancy, the placenta releases some of the hormones which dilutes the effect of insulin. This is known as insulin resistance. So now the pancreas secretes more of insulin to overcome this insulin resistance for the body. Now if a woman during pregnancy does secrete more insulin, the glucose level increases in the body and the woman develops gestational diabetes.
Gestational diabetes greatly depends upon obesity and the ethnicity of the women, but a definite genetic link has not been identified.
This it is a result of the environment control gene expression.