Answer: A. scalp hairs grow constantly throughout life.
Explanation:
Hair is a squamous keratinized epithelium which is consist of multi-layered flat cells. Hair are made up of protein called "keratin".
The statement "scalp hairs grow constantly throughout life" is false because at a particular age or due to several factors scalp hairs stop growing.
Scalp hair growth rate depends on three main factors including sex (female hair grows faster than male), age (hair growth slows with age), and ethnicity (Asian hair grows slower than Caucasian hair).
Scalp hair growth stops because of follicle devitalization when the hair length become two or three feet.
Hence, the correct answer is A. "scalp hairs grow constantly throughout life".
E.the number of amino acids in the protein
Answer:
Ligand A and ligand B can cause same cellular responses in a cell when they are attached to different receptors.
Explanation:
If two same ligands are attached to two different receptors, two different responses will occurs. Such type of response is present in acetylcholine, while when two different ligands attached to two different receptors, same response will occur. This type of response is present in glucagon and epinephrine etc. ligands are responsible for controlling the transcription process when it binds or attached to the DNA molecule of the cell.
messenger RNA (mRNA) carries a transcript (copy) of the DNA's instructions out of the nucleus to the cytoplasm where it attaches to a ribosome.
transfer RNA (tRNA) begins to read (translate) the information on the attached mRNA and corresponding to this information, fetches the appropriate amino acids from the pool of free amino acids in the cytoplasm, and brings them to the ribosome where they are linked into a chain or polymer forming the primary structure of the desired protein.
