Answer:
The two circuits of the cardiovascular system are: Pulmonary Circuit and Systematic Circuit. The pulmonary circuit is shorter than the systemic and is responsible for carrying deoxygenated blood to the lungs from the right atrium, for oxygenation. The systemic circuit is longer and leaves the aortic artery, carrying oxygenated blood throughout the body and nutrients for survival. If less blood were pumped into the systemic circuit, this amount would not be sufficient to compensate for the organism's needs, with the corresponding consequences that this would entail.
It is said that the cardiovascular system is a closed system because blood travels inside a network of blood vessels without leaving them.
Active transport moves from low to high
Answer:
Muscle contraction function.
Explanation:
The nerve endings possess synaptic acetylcholine vesicles ready to be released. The action potential depolarizes the presynaptic terminal and increases the concentration of axoplasmic calcium; Acetylcholine molecules are thus released, so that the concentration of the neurotransmitter at postsynaptic (nicotinic) receptors is temporarily increased. This is followed by post-synaptic membrane depolarization, muscle membrane action potential with increased rnioplasmic calcium concentration, and finally muscle contraction. Acetylcholine is hydrolyzed by acetylcholinesterase and resynaptic at the presynaptic level by cholinecetyltransferase. The etiopathogenesis of myasthenia gravis is autoimmune and there are antibodies against acetylcholine receptors that circulate in the blood, as well as a decrease in the number of receptors on the motor plates, that is, it is produced by the postsynaptic blockage of the myoneural plaque, that generates fatigue and localized or generalized muscle weakness that is characterized by the worsening of the contractile force of the muscle.
The correct answer is option a, that is, It is sometimes sprayed too far from the crops.
The use of pesticides on crops may exhibit a significant threat to the environment, mainly in and nearby to water sources with sensitive ecosystems, sources area, public drinking water, residential areas, and recreational waters.
Aircraft spray of pesticides takes place from a greater altitude than the ground-based equipment and on a major scale, both of these elements may enhance the threat of spray drift.
The benefits of artificial selection is that you've taken the traits that you desire from a plant or an animal that could benefit your own survival. (Much like our ancestors bred the highest/most efficient crops, leaving us in a good farming position today). However, the drawbacks of artificial selection is that you effectively destroy any natural selection or "survival of the fittest" thus reducing the gene pool. If a virus or bacteria was effective against a crop that we bred, it would destroy our entire farming industry (also works with animals that we breed).
