Transamination of an amino acid transfers an amine group to form an α‑keto acid and is catalyzed by transaminases. Some amino acids can be transaminated into compounds that can be used directly in biological pathways, whereas other amino acids need to be converted through several steps. Classify the amino acids into the following two categories.

1. Yields a glycolytic or citric acid intermediate directly upon transamination
2. Requires several steps to yield a glycolytic or citric acid intermediate

a. cysteine
b. histidine
c. asparagine
d. glutamate
e. alanine
f. aspartate

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

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explanation:

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lipid

explanation:

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

i hope this : )