Answer:
Muscle contraction function.
Explanation:
The nerve endings possess synaptic acetylcholine vesicles ready to be released. The action potential depolarizes the presynaptic terminal and increases the concentration of axoplasmic calcium; Acetylcholine molecules are thus released, so that the concentration of the neurotransmitter at postsynaptic (nicotinic) receptors is temporarily increased. This is followed by post-synaptic membrane depolarization, muscle membrane action potential with increased rnioplasmic calcium concentration, and finally muscle contraction. Acetylcholine is hydrolyzed by acetylcholinesterase and resynaptic at the presynaptic level by cholinecetyltransferase. The etiopathogenesis of myasthenia gravis is autoimmune and there are antibodies against acetylcholine receptors that circulate in the blood, as well as a decrease in the number of receptors on the motor plates, that is, it is produced by the postsynaptic blockage of the myoneural plaque, that generates fatigue and localized or generalized muscle weakness that is characterized by the worsening of the contractile force of the muscle.
Its atomic mass determines its properties? hope this is correct
Answer:
Mutations of enzymes involved in nucleotide excision repair.
Explanation:
- Xeroderma pigmentosum is a genetic disorder and the person suffering from this disorder is sensitive to ultraviolet light due to the disability of the enzymes involved in nucleotide excision repair which prevents DNA damage caused by ultraviolet light.
- Thus, the individuals are sensitive to the exposure of UV and suffer severe problems when exposed to sunlight.
- The major cause of the disorder is the inability to repair DNA damage caused by exposure to sunlight due to the mutation in an enzyme involved in nucleotide excision repair.
- Nucleotide excision repair is a DNA repair process that can excise out single-stranded DNA that is damaged by UV.
- UV exposure leads to the addition of bulky adducts in the DNA known as thymine dimers. The enzymes of NER are involved in the removal of these adducts by excising out a segment of DNA that contains such lesions.
- However, in the case of XP, the mutations make this repair system non-functional or partially functional and thus, the individual becomes highly sensitive to UV exposure.
Answer:
Explanation: DNA is the information molecule. It stores instructions for making other large molecules, called proteins. and the function of DNA is To carry out these functions, DNA sequences must be converted into messages that can be used to produce proteins, which are the complex molecules that do most of the work in our bodies.
