Answer:
4 reasons here:
Explanation:
1) Adventure; boredom causes them to look for excitement, even if it's detrimental to their health.
2) Peer pressure;research shows that risk-taking among teens doubles when peers are around.
3) media;easy to guess, shows a lot of risky behaviour in glamorous or admirable ways.
4) Poor self-esteem; bullying can lead to poor self-esteem and higher chance of the victim becoming depressed and taking substance to cope with the depression, also leads to err, self-death
Answer:
A. Molecular changes such as extracellular signals on extracellular ligands can result in quick changes in cell behaviour. One example is insulin. Upon insulin binding on the receptor on the cell membrane, the cell release GLUT4 transporters (for muscle cells) to increase uptake of glucose.
B. Slow changes in cell behaviour can be observed for other lipophilic hormones or intracellular receptors such as glucocoortoid or estrogen which reacts with receptors in the cells.
C. Insulin is required to maintain a constant blood glucose level and hence levels of insulin has to be mediated in correspondence to the blood glucose levels. Fast acting signalling is thus required for homeostasis of blood glucose levels. Where for such lipophilic hormones such as steriods, glucocortoid, these hormones tend to have a longer lasting effect and hence results in a slow change.
Answer:
e.DDT
Explanation:
DDT is biologically magnified and concentrated as it moves through the food web. This increase in concentration is due to Metabolism of DDT which excretes more slowly than the nutrients which moves from one trophic level to next. so DDT accumulates in the body especially in the Fats.
Some species of penguins, such as chinstrap penguins, depend on open water for their survival. Other species of penguins, such as Adélie penguins, depend on ice. Over the last 20 years, the population size of chinstrap penguins has increased, and the population size of Adélie penguins has decreased. An increase in global air and water temperatures likely caused <span>these changes in population size.</span>
<u>Answer:</u>
<em>Mitochondria appear in the greatest numbers in cells that are</em><em> </em><em><u>Muscle cell.</u></em>
<u>Explanation:</u>
Mitochondrion is the power house of the cells. It releases the energy need for the cells. So mitochondrion is found in large number in muscle cell because muscles are the component of our body that needs large amount of energy.
Muscles need to be frequently moved in our body so large number of mitochondria helps in providing the enough energy for the proper muscle movement.
