Answer: D. Keratin
Explanation: Keratinocytes (pronounced: ker-uh-TIH-no-sites) make keratin, a type of protein that's a basic component of hair, skin, and nails. Keratin in the skin's outer layer helps create a protective barrier.
Answer:
Spring tides occur when the sun, moon and earth are lined up, and it causes high and low tides to be much higher (moon is full/new). Neap tides occur when the sun, moon, and earth form a right angle this causes regular high and low tides to be much lower (first quarter and last quarter moon). The moons gravity and suns gravity pull the earths crust and ocean water.
Explanation:
The substance that helps keep the integrity of the bacterial cell wall intact is known as the peptidoglycan. Others also refer to is it as murein or mucopeptide. The bacterial cell wall is necessary for survival because of the high internal pressure present inside of bacteria. Under normal conditions, if the cell wall is removed the bacterial cell will burst.
The peptidoglycan is a layer that can be used to distinguish gram positive bacteria from gram negative ones. G(+) bacteria have a thick layer of this while G(-) have a thinner ones.
<u>Answer</u>: There are numerous factors that influence the behavior and physiology of an individual animal/plant etc. By doing the study in their natural environment, you remove any possible bias caused by this.
Furthermore, an individual's behavior will differ in an artificial experimental setup compared to that observed in a natural setting. When possible, studying the subject in its natural environment is the best experimental method.