Option D – amphibians may use their skin for gas exchange is the characteristic feature of amphibians that differs from reptiles.
Explanation:
The amphibian skin is moist, thin and marbled and supplied by blood vessels running on its surface. The moisture present in the skin dissolves the oxygen present in its surrounding which is absorbed by the blood vessels. Special glands help the amphibians to keep the skin moist.
The very thick and tough scales present on the reptiles prevent them to absorb oxygen through their skin. Hence, they breathe and respire through their lungs.
Amphibians have three-chambered heart. They do not develop amniotic eggs. Adult amphibians although spend much time on land, they breed only in water due to the absence of amniotic sac
.
Los pulmones y el sistema respiratorio permiten la entrada del oxígeno del aire en el organismo, así como la expulsión de dióxido de carbono al espirar. La respiración es el término que se utiliza para denominar el intercambio de oxígeno procedente del entorno por el dióxido de carbono que se produce en las células.
Answer:
Answer is 2. Fibroblasts fail to divide.
Explanation:
Tissue culture experiment is the experiment where tissues are grown in an artificial medium. This involves the use of growth medium such as agar or broth. This process help to produce needed tissues in a short period of time.
Fibroblasts are cells which are found in the collective tissues, and they produce collagen. The collagen produced by the Fibroblasts play important role in tissue repair. Fibroblasts are regarded as the main cells in the connective tissue.
Note that, PDGF, which is Platelet -derived growth factor in full, is a growth factor regulating cell growth and it's division.
C) Heterozygous In a punnet square it will have a 100% chance of being heterozygous dominant.
The correct answer is - temperate.
The temperate climates can simply be described as climates with milder temperatures. These climates have changes of seasons, four of them, spring, summer, autumn, and winter. The springs and autumns tend to have mild temperatures, the summers are warm, and the winters are cold, but the highest and lowest temperatures do not come close to the extremely high temperatures in the tropical zone, or extremely low temperatures in the high latitude zones. So these climates have temperatures that are in between the extremes of the low and high altitudes, thus they are milder climates.
