Answer:
Positive feedback is used to build more contractions.
Explanation:
Positive feedback mechanism in humans is also observed during childbirth which is induced by the pressing of the ovarian wall by the baby.
The pressing sensation is passed to the brain via different nerves, and in response, the brain stimulates the pituitary to produce oxytocin.
Oxytocin is responsible for the contractions of the uterine muscles which cause the movement of the fetus towards the cervix, further increasing the stimulus.
The positive feedback loop continues until the baby is born.
The brain imaging technique you refer to is the MEG.
Answer:
The statement that is correct is that all cells have the same genes, but different genes are active in different cells.
Explanation:
Differentiation or specialization is a function that cells possess and is what allows them to have different types of cells and tissues.
Cell differentiation depends on genetic regulation, a mechanism that determines the specific genes that are expressed in a cell or tissue type.
All cells contain the same DNA, which is organized into chromosomes and contain the genes that determine specific characteristics. <u>There is cell differentiation because some genes can be expressed and others are suppressed, all due to genetic regulation</u>.
The other choices are wrong because:
- <em>The eyes look different from the liver, because they have the same genes, but only some are expressed.
</em>
- <em>Differentiated cells and tissues do not lose their genes.
</em>
- <em>All cells have DNA.</em>
Answer:
See below
Explanation:
There are several reasons that genetic variation occurs. Some of them are as follows: mutation, random fertilization, recombination event during meiosis etc. The way in which this variation in genetics is distributed is in a continuous way. In case of the human species, it is reported that 85% of all variation is within a certain population, while the remaining 15% of genetic variation is between populations.
Cell nucleus chromosome gene nucleotide base subunit atom
