Gynecomastia is an increase in the size of the mammary gland in men. The condition can occur in one or both breasts. It starts as a small mass under the nipple, which can be sensitive. One breast can be bigger than the other. Its cause is an imbalance between the stimulatory effects of estrogen (female sex hormones) and the inhibitory effects of androgens (male sex hormones) in the breast tissue, when the first ones increase, or the second ones descend.
Gynecomastia is a problem relatively common in the population, and there are three prevalence peaks throughout life:
Newborns: Between 60 and 90% of newborns have gynecomastia, produced by the passage of maternal estrogens through the placenta. It is a transient gynecomastia that disappears in about 2-3 weeks.
Puberty: Gynecomastia in puberty affects mainly young people aged between 10 and 14 years, and is due to the transient and physiological increase in estrogen that occurs at this age.
Elderly: Is due to an increase in fatty tissue with a greater peripheral aromatization ( a process that occurs in adipose tissue and that involves the conversion of androgens into estrogens), a decrease in the production of testosterone by the testes and the use of drugs.
Answer:
Diffusion is the process in which molecules and ions move from a region of high concentration to low concentration. Its also how cells transport waste out of the cell and nutrients into it hence being very crucial. Diffusion also occurs without the expenditure of extra energy using a procedure known as passive transport. (Osmosis is a form of diffusion but deals with water exclusively).
Examples of where diffusion is important;
In the intestines - Digested food molecules such as amino acids and glucose move down the concentration gradient from the intestine into the bloodstream. Wastes such as carbon dioxide or urea travel via diffusion from the body's cells to the bloodstream.
Osmosis plays a major role in living organisms. It aids in the transportation of nutrients from cells to cells and also helps to remove the waste's metabolic products from the cell. The purification of blood in the kidneys is also dependent on the process of osmosis.
Answer:
A. Chipmunks sleeping underground through the winter
Explanation:
A seasonal change in the behavior of a living organism is a change that occurs every year at a particular time. The reasons for the occurrence of such changes are so that the organism has advantage in survival in the environment. In this case we have the chipmunk that sleeps underground through the winter. We have an animal which exhibit a seasonal change every year, during the winter period. The reason for this is that the chipmunks have very quick metabolism, so if they are active during the winter they will starve because of lack of food. Instead, the chipmunks have evolved to hibernate during the winter, thus slowing down the work of their hurt during the winter and sleep, until the spring comes.
I think it is B because a cladogram shows how species are related AND also shows the evolution between them.
Answer: How timothys parents were different races and it made him greek and jewish.
Explanation: Timothy came from a mixed racial background, in which his mother was Jewish and his father was Greek;
