Answer:
Underneath both the soil and the ocean, Earth's outer layer is made of sand and water. Underneath both the soil and the ocean, Earth's outer layer is made of hard, solid rock.
Answer:
Sharp-spined cactus
Explanation:
Given, that N allele is required for the production of spine and S allele will produce sharp sines.
True breeding sharp spined cactus: NNSS
spineless cactus: nn__ ( we can't fix the allele for second gene since it has not been mentioned as true breeding )
Their progeny: NNSS X nn__ = NnS_
So the progeny is going to be sharp spined because both the dominant alleles N and S are present.
The answer is the
population size. The chance has a role
in determining whether a given individual survives and reproduces and the
alleles in the offspring are a sample of those in the parents. it is the change
in the frequency of an existing gene variant (allele) in a population due to
random sampling of organisms. Genetic Drift or another term for allelic drift
or the Sewall Wright effect.
Electrons are the smallest of the three particles that make up atoms. Electrons are found in shells or orbitals that surround the nucleus of an atom. Protons and neutrons are found in the nucleus. They group together in the center of the atom.
Answer:
True
Explanation:
Some deviations from normal homeostasis activate the positive feedback loops to control the conditions which are otherwise regulated by negative feedback mechanisms.
For example, the blood levels of respiratory gases and H+ ions are regulated by a negative feedback system via chemoreceptors. The increased partial pressure of carbon dioxide gas and lowered pH or lowered partial pressure of oxygen in the blood are sense by central and peripheral chemoreceptors which in turn activate the neurons of the dorsal respiratory group (DRG).
The activated DRG triggers an increased in the rate and depth of the breathing to facilitate the inhalation of more oxygen and exhalation of CO2 to restore the normal levels.
However, hypocapnia inactivates the chemoreceptors and does not allow negative feedback to restore the normal CO2 levels in the blood.
Under such conditions, the positive feedback loop stimulates the DRG neurons more strongly in response to the increased partial pressure of CO2 above the normal levels than when the partial pressure of oxygen falls below the normal level. These dangerously lowered oxygen levels may also cause fainting.
