Answer:
Option A
Explanation:
Thyroid is primarily caused by lack of iodine but there are other reasons as well that lead to increased size of the thyroid gland. Some of these reason is
a) over- or underproduction of thyroid hormones
b) Nodules in the glans
Some times, due to overstimulation immune system itself attack the thyroid gland thereby producing excess thyroxine and hence causing the thyroid to swell
Thus, Option A is correct
Answer: Single covalent bond in the long hydrocarbon chain.
Saturated fatty acids are long chains of hydrocarbon ( with single covalent bond) ending with the carboxylic group (-COOH). This means those fatty acids which possess only single bonds in their chemical structure are called as saturated fatty acids. They are densely packed, which makes them solid at room temperature.
Example- Lauric acid ( present in coconut oil). It has 12 carbon atoms in its chemical structure.
Answer:
In this image the bird is eating an insect off of a leaf that is easy to see whereas the insect on the other leaf is camouflaged and still alive. This helps illustrate the concept of natural selection because the camouflage insect is able to survive longer and therefore reproduce more.
<span>Intrinsic factor is a glycoprotein principally secreted by the parietal cells of the stomach. This secretion is needed to produce mature erythrocytes. Its secretion is governed by the same biochemical processes that regulate acid secretion and its action is to assist in the absorption of vitamin B12.</span>
