Answer:
Osmosis is a process in which molecules pass from semipermeable membrane.
Explanation:
Osmosis is a biological process. The solvent molecules pass through semipermeable membrane and then solute particles move through the membrane with the help of water. These molecules are not capable of passing through the membrane in absence of water.
Answer:
The correct answer will be option-B.
Explanation:
Sertoli cells are the large somatic cells present in the testis which helps in the formation of spermatozoa. The Sertoli cells create a suitable environment for the production and maturation of the sperms as they produce certain molecules which nourishes the sperms.
The Sertoli cells act as a barrier between the testis and blood and secrete enzymes like inhibin. They eliminate the apoptotic germ cells and also produce seminiferous fluid to nourish the sperm. They do not play any role in primary spermatocytes.
Thus, Option-B is the correct answer.
Answer:
Linings of hollow organs
Explanation:
Smooth muscle cells are usually found in the lining of hollow organs such as all arteries and veins, wall of stomach, uterus, urinary bladder, digestive system etc. The cells of these linings are spindle shaped and consist of a nucleus at the center which lacks striations.
They work as a housekeeper and are under involuntary control except the heart. They lack striation because of irregular arraying of actin and myosin filament along the length of the cell.
Answer:
The mentioned case is an illustration of the missense mutation. A missense mutation is a kind of nonsynonymous substitution, that is, it is a mutation in which a variation in a solitary nucleotide leads to the formation of a codon, which encrypts for a distinct kind of amino acid.
When a missense mutation takes place within a DNA, a modification in one of the RNA codon sequences results at the time of transcription. This change in codon will ultimately result in the formation of a different amino acid, which gets presented within a protein at the time of translation. Like in the given case, a change in codon resulted in the substitution of the amino acid tyrosine with an amino acid cysteine.
The correct answer is soul fertility. Soil fertility refers to the ability of soil to sustain agricultural plant growth, i.e. to provide plant habitat and result in sustained and consistent yields of high quality.[1] A fertile soil has the following properties:[2]
The ability to supply essential plant nutrients and water in adequate amounts and proportions for plant growth and reproduction; and
The absence of toxic substances which may inhibit plant growth.
