During exercise stroke volume increases because more blood is sent back to the heart due to the muscles squeezing blood in the veins
Answer:Radiometric dating allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata. The correct option is D.
Explanation:
Radiometric dating was first used by geologist after being published by Bertram Bollywood in 1907. During volcanic eruption, some minerals ( carbon) are trapped within the volcanic strata. These minerals are made up of radioactive isotopes which are unstable as they form decay products with a known constant rate of decay. This enables them to :
- access information about the absolute age of rocks,
- date a wide range of natural and man-made materials
- know even the age of earth. I hope this helps. Thanks
Answer:
The correct answer is The cells do not have proper receptor.
Explanation:
During paracrine signaling a signaling molecules are generated from one cell.The generated signaling molecule then binds to the receptor of neighboring cell to carry specific signal from donor cell to the acceptor cell.
But the signaling molecules will not bind to the cell that is producing it because that producing cell do not contain proper receptor to bind that signaling molecule.
The binding of signaling molecule to the receptor of its producing cell occur during autocrine signaling.
Answer:
The correct answer is option a, that is, sympatric speciation.
Explanation:
Speciation, which takes place when two groups of similar species live in a similar geographical location, however, they evolve distinctly unless and until they no longer interbreed and are regarded as different species is termed as sympatric speciation.
Sympatric speciation is not similar to other kinds of speciation, in which the formation of a new species takes place when a population gets differentiated into two groups because of migration or geographic barrier. The sympatric speciation can be witnessed in various distinct kinds of species. Thus, the given case of monkeys is an illustration of sympatric speciation.
