The theory regarding the transition occurring in a population in a country or a region.
Answer:
Most commonly, people get or transmit HIV through sexual behaviors and needle or syringe use. Only certain body fluids—blood, semen , pre-seminal fluid, rectal fluids, vaginal fluids, and breast milk—from a person who has HIV can transmit HIV.
Explanation:
Answer: The correct option is E ( Intermediate filaments are unpolarized).
Explanation:
Intermediate Filaments are usually associated with cells that can withstand mechanical stress which includes claws of animals, hair and makes up the dead remnants of the epidermal cell of the skin. Therefore without the supporting network of intermediate filaments, an epithelium remains intact but the cells are prone to damage by abrasive forces.
Intermediate filaments are so named because they are thicker than actin filaments and thinner than microtubules or muscle myosin filaments
The properties or characteristics of an intermediate filaments that explains the lack of motor proteins is as a result of its subunits which are elongated, not globular and are associated in an anti-polar manner. Therefore, the overall filament has no polarity, and therefore no motor proteins move along intermediate filaments
B - Enzymes act as catalysts because they lower the activation energy
Answer:
Testes and ovaries produce two types of hormones:
androgens (male sex hormones)
estrogens (female full hormones)
In each type of gland, both types of hormones are secreted only in different amounts: the ovaries secrete more estrogen than the androgen hormones, and the sperm inversely.
Explanation:
In testicular tissue, Leydig cells produce androgen hormones: androsterone and testosterone. The ovaries produce a group of estrogen hormones and progesterone. These hormones exert their effect at puberty when the glands are activated. At puberty, the pituitary gonadostimulins activate the sex glands, whose activity leads to the development of secondary sex characteristics (the appearance of first menstruation in girls, beards and mustaches in boys, etc.).