All other organs, ducts, and glands in the reproductive system are considered secondary, or accessory, reproductive organs. These structures transport and sustain the gametes and nature the developing offspring.
Hope this helps!
Answer:
Open circulatory system:
Relies on the heart to keep blood flowing
Used in all vertebrates
Sorry thats all i know :)
Bird migrations began with the recession of the glaciers during the ice age. You will notice a great increase in insects in the spring time and early summer.The birds moved North to take advantage of this increase in the food supply that followed the warming in the spring and early summer. Their reproductive organs temporarily developed so they could lay eggs and raise a family. Look at the early flush of Night crawlers in the moist times of the early rains. By mid summer most of the insects have matured, mated and died. Their eggs have hatched and turned to larva and moved underground until next spring. The shortening of the days causes the reproductive functions to decrease and signals the birds that the food will soon become scarce. They move back to the area that makes it the easiest to find food and avoid freezing. which of course is the warmer climates nearer the equator. Not all birds move past the Tropics at approximately 30 degrees. Some like Chickadees may move down from Mi or Mn or Canada only as far south as Indiana. Some migrations may be quite short. For example from the mountains down to the plains. They don't generally reproduce in the warmer winter climes they migrate to. In the spring time they migrate along paths of the retreating glaciers. As the climate warms away from the tropics the birds follow the emerging insects etc to the birds selected breeding grounds.with increased insects and longer days to feed the hatching's. It is necesary to understand why they move to cooler climates in the summer to under stand why they move to eh warmer ones in the fall. As the days shorten the food supply dwindles and the babies have fledged. They move to warmer climates in winter to rest and refuel for the next years migration.
(4) produce new varieties of domestic animals
Although (1) (2) and (3) are modern-day uses of selective breeding, they are relatively recent developments in human history, only used for the past century or less. (4) is correct because the selective breeding of domestic animals to produce new varieties of dogs, cats, etc. has been used for thousands of years, dating back to the ancient Chinese and Egyptian dynasties.
Answer:
The DNA in genes is transcribed into RNA and translated into proteins
Explanation:
The sequence of DNA in a gene is transcribed into a messenger RNA (mRNA). This sequence of this mRNA is translated into a sequence of amino acids that form a protein.
The sequence of DNA in a gene directly affects the amino acids, and therefore the structure and function of, a protein.
