a neurosecretory cell in the hypothalamus.
Answer:
1. sperm cell
2.testicles
3.egg
4.ovary
5.fertilization
6.fertilized egg = foetus
Explanation:
Answer:
The correct option is <em>B) ultraviolet region, especially below a wavelength of 320 nm.</em>
Explanation:
Ultraviolet light carries an enormous amount of energy in it. It is invisible to the human eye. When UV light with enormous energy and wavelength lesser than 320nm, hits the DNA, it causes changes in the structure of the DNA. Mostly, it affects the thymine nitrogenous base regions and forms pyrimidine dimers. The structure of the DNA changes on all the sites where dimers form and hence, they cannot be properly transcribed.
The overuse of antibiotics. is a contributing reason behind emerging disease?
Out of the following given choices;
A. DNA accumulates mutations at a regular rate
B. known mutation rate for a gene
C. the number of differences in DNA sequences for a gene in two species
D. the same gene identified in two species
E. All answers are corrects
The answer is E. The molecular clock used rates of mutation to determine the prehistoric time when two species that share a common ancestor diverged. The benchmarks for determining the mutation rate are often fossil or archaeological dates.
