The right answer is vein (it contains blood and has valves).
The infra-cardiac veins of small and medium caliber possess this system of fight against gravity. The valves consist of a dense connective tissue, surmounted by endothelial cells, corresponding to a fold of the intima. They allow blood circulation in the sense organ / heart but prevent venous reflux.
Once energy from the Sun gets to Earth, several things can happen to it: Energy can be scattered or absorbed by aerosols in the atmosphere. ... Light colored surfaces are more likely to reflect sunlight, while dark surfaces typically absorb the energy, warming the planet.
Skin remains red after a bad sun burn because:
inflammation causes increased blood flow.
Explanation:
When our skin is exposed to sun rays , the epidermal layer starts getting damaged. The damage to the cell caused by sun rays triggers the melanin secretion. Increased secretion of melanin results in darkening of the exposed region .
However, the damage and inflammation to the skin increases blood flow to the skin, this causes reddening of the skin.
Answer:
eukaryotes that ensures that the number of chromosomes will not double from parent to offspring when gametes fuse during fertilisation. Homologous pairs of chromosomes separate in meiosis I, so the gametes are haploid (n), and each gamete receives only one member of each chromosome pair.
Explanation:
I hope this helps!
