It is true that z<span>oning laws may designate parcels of land for specific uses, but sometimes the economic benefit of developing wetlands, grasslands or forested areas overrules the protection of such land.
This is especially true if a rare plant or something thought to be extinct starts growing there - then the nature cannot be disrupted so as to make a building or something else there. </span>
Answer:
Answer:
THE GREAT SPERM RACE:
A sperm's race to fertilize an egg is not so easy. Out of about 250 million sperm ejaculated into the human vagina during intercourse, not more than one in a hundred will survive the Great race to the end due to the hurdles it has to face in the hostile, ACIDIC CHAMBER to the cervix (it has hundreds of tiny branching tunnels that can trap, crush and slowly kill sperm).
If ovulation is not occurring soon the sperm will "drown in a thick flow of cervical mucus
Answer:
The statement that best describes the vascular tissue in seed plants is that xylem carries water and nutrients from the roots to the rest of the plant.
Explanation:
Xylem corresponds to the tissue of the vascular plants that is responsible for the transport and distribution of liquids necessary for their development.
The main function of xylem is to<u> carry water, mineral salts and other nutrients -in the form of raw sap- from the root to the whole plant</u>, forming a network similar to the circulatory system of higher animals.
A cell that just fertilized has to divide 6 times to form a 64 cell blastomere.
<u>Explanation:</u>
Human reproduction begins with the fusion of male gamete sperm and female gamete ovum. The fusion of sperm and ovum forms the zygote that is diploid. The zygote then undergoes mitotic division to develop into embryo.
The zygote first divides into two and the two individual cells divide again to form four individual cells and so on. Thus the number of cells after each division can be represented by the equation
where n is the number of divisions. in the question it is given that the blastomere has 64 cells.
n=6
This means that the fertilized cell has to divide 6 times to develop into 64-celled blastomere.