Answer:
<h2>
Mitosis and meiosis are the ways of cell division which result daughter cells for growth, development and reproduction.
</h2>
Explanation:
Mitosis and meiosis result daughter cells for growth, development and reproduction in the living world.
Mitosis results two similar daughter cells which are generally for growth and development. In asexual mode of reproduction, mitosis helps in increasing the number of cells.
Meiosis occurs in germ cells, and in meiosis, one diploid cell produce four haploid cells.
Meiosis results variations by independent assortment and by crossing over and it helps the sexual mode of reproduction. During fertilization, the resultant daughter haploid cells unite and retains the diploid number of chromosomes.
Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.
Answer:
The correct answer is - tight junctions.
Explanation:
Tight junctions are one of the cell-cell junctions that make a barrier to the passage of material which is a present in epithelia. This barrier is impermeable to most of the materials with soluble molecules. This barrier is made up of the occludin and claudin proteins.
Tight epithelia have tight junctions and examples of such junctions are the distal convoluted tubule or DCT, and the collecting duct of the nephron in the kidney.
Thus, the correct answer is - tight junctions.
<u>Answer</u>: Cystic fibrosis is a genetic disorder that causes thick mucus secretions.
<u>Explanation</u>:
- <em>Cystic fibrosis</em> is a genetic disorder caused by mutations in a gene that makes a protein called CFTR (cystic fibrosis transmembrane regulator).
- The CFTR protein normally functions as a channel for transport of chloride ions in cells responsible for mucus production.
- A person suffering from cystic fibrosis produces abnormal CFTR protein or no CFTR protein at all.
- This is the reason that thick, sticky mucus is produced instead of the thin, watery kind.
