MRNA is a single-stranded molecule that carries genetic code from DNA in a cell's nucleus to ribosomes, the cell's protein-making machinery.
Answer: The correct answer is D. the central nervous system and the peripheral nervous system.
The nervous system is a complex system that is made up of nerves and nerve centers in different organisms that carries messages to and from the brain and the spinal cord to send them into various parts of the body.
It is primarily divided into-
1) CNS that is central nervous system ( made up of brain and spinal cord). The CNS is responsible for the voluntary functions of the body.
2) PNS that is peripheral nervous system ( possess cranial and spinal nerves arising from brain and spinal cord respectively). It controls the involuntary functions of the body.
Answer:
Blood is carried away from the heart by arteries. Blood that is rich in oxygen. Blood that is low in oxygen is returned to the heart by veins. there is more pressure in arteries than in veins.
Answer:
The correct answer is - decreased population size at all levels.
Explanation:
A decrease in the productivity of producers of an ecosystem will lead to a decrease in all other organisms of the ecosystem including top-level consumers to the bottom-level producers due to the fact that producers provide energy and food to primary consumers.
It is because they are the only organisms that convert the sunlight to usable energy and food that transfer from one trophic level to other, so if the population of producers or their productivity will decrease then there will be decreased population size at all levels.
