Distillation is one of the processes that are used in the laboratory to remove impurities from substances. Distillation employs the differences in the boiling points of two liquids to separate them. The distillation apparatus must have an opening to the atmosphere at an end in order to avoid developing a dangerously high pressure within the system when heat is applied.<span />
Answer:
The overall strategy employed in the catabolism of the carbon skeletons of the 20 amino acids is conversion to citric acid intermediates such as acetyl-CoA
Explanation:
The breakdown of the different carbon skeletons of the 20 amino acids is strategically channelled towards the citric acid cycle. Six major products are obtained in the catabolism of the carbon chain of amino acids and these products all enter the citrc acid cycle. The six major products are acetyl-CoA, α-ketoglutarate, succinyl-CoA, fumarate, oxaloacetate and pyruvate.
The amino acids that are broken down completely into acetoacetyl-CoA and/or acetyl-CoA are said to be ketogenic since they yield ketone bodies in the liver.
The amino acids that are broken down into α-ketoglutarate, succinyl-CoA, fumarate, oxaloacetate and pyruvate can be converted to glucose and glycogen and are said to be glucogenic. Pyruvate can further be converted to either acetyl-CoA or oxaloacetate. Some amino acids though are both ketogenic and glucogenic, e.g. tryptophan, threonine.
The T lymphocytes capable of killing invading cellular organisms such as bacteria, protists, or fungi are cytotoxic T cells also known as CD8+ cells. These cells are capable of recognizing whether a cell has a major histocompatibility complex I (MHC I) surface protein or not. Those with absent MHC I surface protein will be killed by the cytotoxic T cells. Those with the MHC I surface protein expressing an invading antigen will also be killed by cytotoxic T cells. Those with the MHC I surface protein without an antigen will be spared by the cytotoxic T cell.
Answer:
Faciliated diffusion, which requires a carrier protein but no cellular energy. The energy for this process is provided by the concentration gradient of the substance being transported.
Explanation:
Physiological effects of abscisic acid
Abscisic acid acts as growth inhibitor and induces bud dormancy in a variety of plants. 2. ABA is a powerful growth inhibitor. It causes 50 per cent inhibition of growth of oat seedlings.
