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.
Answer:
D. number of individuals in a species
<u>Definition:</u>
The sex hormone and endogenous steroid present in human and other species ' menstrual cycle, pregnancy, and embryogenesis are known as "Progesterone" while the primary sex hormone in females responsible for the development and control of the female reproductive system and for the characteristics of secondary sex is termed as "Estrogen" or "oestrogen".
<u>Progesterone Effects:</u>
- Progesterone has a variety of physiological effects which are exacerbated when estrogens are present for an instance in breast tissue, where estrogens permits progesterone to mediate lobuloalveolar development.
- Progesterone has main effects on human sperm by non-genomic signals, as they move through the female tract before fertilization.
- Progesterone is called "hormone of pregnancy" as transform the endometrium to its secretory stage for uterine implantation, decrease the maternal immune response to permit for the acceptance of the pregnancy during implantation and gestation, prevent preterm labor, inhibits lactation during pregnancy etc.
<u>Estrogen Effects:</u>
- Effects structure of human and categorize them as male and female, while females have three kind of estrogen: Estrone (weak and found in women after menopause), Estradiol (strong and it is steroid produced by ovaries ) and Estriol (weakest and waste product after body produces estradiol).
- It effects ovaries, vagina, Fallopian tube, uterus, cervix and mammary glands.
- It triggers the release of an egg due to high level during halfway of cycle but decreases after ovulation.
<u>Similarities between progesterone and estrogen: </u>
Progesterone and estrogen as such do not have similar function but work with coordination as both are need for menstrual cycle functioning and regulation. Estrogens usually travel in fluids through the bloodstream, communicate with cells in the body's various tissues, and provide a message or guidance while progesterone helps to balance pregnancy period and to implant an egg in uterus.
