Biology - Online Test
In the Enteric nervous system :
i. neurons of Myentric plexus regulates glandular secretions in GI tract.
ii. neurons of Meissner’s plexus regulates peristaltic waves.
column A
a) cristae
b) cerumen
c) organ of corti
d) maculae
column B
i) responsible for lubrication and protection
ii) responsible for dynamic equilibrium
iii)responsible for static equilibrium
iv) responsible for hearing
The genetic code is the set of "rules" that a cell uses to interpret the nucleotide sequence within a molecule of mRNA. This sequence is broken into a series of three-nucleotide units known as codons.
The three-letter nature of codons means that the four nucleotides found in mRNA — A, U, G, and C — can produce a total of 64 different combinations. Of these 64 codons, 61 represent amino acids, and the remaining three represent stop signals, which trigger the end of protein synthesis.
Because there are only 20 different amino acids but 64 possible codons, most amino acids are indicated by more than one codon. ( however, that each codon represents only one amino acid or stop codon.).
This phenomenon is known as redundancy or degeneracy, and it is important to the genetic code because it minimizes the harmful effects that incorrectly placed nucleotides can have on protein synthesis.
Read the following statements :
i. Every 100 ml of deoxygenated blood delivers about 4 ml of to the alveoli.
ii. 30% - 40% of is transported to the alveoli as carbamino-haemoglobin.
iii. At respiratory surface diffuses from venous blood into alveolar spaces.
