Answer:
spider with second option (spiders have an open circulatory system.)
earthworm with first option
starfish with forth option
Explanation:
Answer:
A)11,460 years
Explanation:half of a radioactive element represent the time take for half of it's components to dissociate or disintegrate.
For carbonn14 that undergo an emmision to form a stable carbon 14,it moves thus
14C(1 part) ______14C(0.5 parts)_____14C(0.25parts)
i.e it undergo two radioactive decay which means two half lives .
Since each half life is 5780 years ,the age will be 2×half lives= 2×5780=11,460 years
Answer:
I would say B.
Explanation:
A would only fix biodiversity temporarily, until humans come and wipe them out again. C is just kind of impossible, and containing them could also be problematic. D is also unreasonable, and some animals would not be able to thrive in new ecosystems. B would help save the environment, which would save the animals, which would help biodiversity.
Answer:
True
Explanation:
Geneticists have discovered that all human embryos start life as females. In the early development in the embryonic stage, this is true both for humans and mammals. This changes only at the 2nd month (in the case of humans, since different mammals have different gestating periods) if the embryo can elaborate enough androgens (dominant male hormone) to offset the maternal estrogens (dominant female hormone) then, maleness develops.
Explanation:
Having filtered out small essential molecules from the blood - the kidneys must reabsorb the molecules which are needed, while allowing those molecules which are not needed to pass out in the urine. Therefore, the kidneys selectively reabsorb only those molecules which the body needs back in the bloodstream.
