Answer:
Explanation:
The sperm reproduction startes in the testicles.Sperm are produced in the testicles and develop to maturity while traveling from the seminiferous tubules through the epididymis into the vas deferens. As a male and female have sexual intercourse their are millions of sperms released which travel from the seminiferous tubules through the epididymis into the vas deferens as that happens the sperm enters throught the partner from here it takes its journey to the egg using ts tail to swim the first sperm to reaches the egg then uses the acrosome, which is a specialised Lysosome that releases enzymes so that the Sperm Cell can penetrate the Ovum Coat of the Egg.It breaks through and forms a baby.
Hope this helps
Answer:
The correct answer is option D.
Explanation:
Thermohaline circulation is the circulation of currents in the deep ocean due to the density of the water which is controlled by heat and salinity. Water in the ocean posses layers or defined boundaries based on the density which provides driving force to the deep ocean currents.
Formation of these layers is due to the sinking of the cold water in the basin which and ice formation which leaves the salt in the seawater ,therefore, increasing salinity. This increased salinity increases its density and the surface water is replaced by the sinking water causing deep ocean currents.
Thus, option D is the correct answer.
Answer: dust, gas, dark matter,round
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
.
