Answer:
The gonads are reproductive organs responsible for the production of <u>gametes (sex cells) in their external secretion and in their internal secretion, hormones that exert their action on the organs involved in reproductive function.</u>
Explanation:
Gonads are glands that are part of two body systems: the endocrine system and the reproductive system; and there are two types of gonads: male and female, the first are the testicles and the second the ovaries and both produce steroid hormones (derived from cholesterol) exactly the same as those produced by the cortex of the adrenal glands.
The correct answer is A. A burst of speciation
Explanation:
Adaptative radiation is part of evolution and occurs when a single organism or species diversify into a wide range of species (speciation), this process is called "adaptative" because the speciation occurs due to changes in the environment that make challenging survival usually due to the reduction of resources available and therefore organisms change to adapt to new conditions. Additionally, in adaptive radiation, the new organisms share traits with their common ancestor but also have different and unique traits. Considering this, it can be concluded adaptative radiation a burst of speciation.
B) Endocrine disruptors mimic hormones that regulate critical biological processes
Answer:
The difference is:
a) Positive feedback increases a change while negative feedback reduces a change.
b) Positive feedback occurs specific situations while negative feedback occurs in the body.
c) Positive feedback break down the homeostasis while negative feedback maintain the conditions of homeostasis.
d) Positive feedback has less frequent mechanism while negative feedback has more frequent mechanism.
e) Positive feedback enhances change while negative feedback resists change.
f) Positive feedback has a wider range while negative feedback has a narrow range.
Explanation:
Hope they help.
Answer: Crossing-over allows the genes that come from each parent to recombine before they are passed on to future generations because chromatids of homologous chromosomes mate and exchange sections of their DNA.
Explanation:
Chromosome crossing-over is the process by which chromatids of homologous chromosomes mate and exchange sections of their DNA during prophase I of meiosis, when pairs of homologous chromosomes, or of the same type, are aligned. The chromatids of the homologous chromosomes break off in the chiasmas and rejoin to allow recombination of the linked genes. So it occurs when regions at chromosome breaks mate and then reconnect to the other chromosome. <u>The result of this process is an exchange of genes, called genetic recombination</u>.
This allows the genes that come from each parent to recombine before they are passed on to future generations. Then, <u>it is an important source of genetic variability</u>, since it involves an exchange of segments between homologous chromosomes during the development of gametes. <u>This process allows that the descendants of an individual are genetically very different</u>, since it is very unlikely that an individual produces two equal gametes, because all of them have different segments of the homologous chromosomes.
