In HIV-infected patients, there is a gradual loss of CD4+ T cells over time. These cells, also called T helper cells, organize the immune system's attack on disease-causing invaders, like Salmonella.
Answer:
Salinity in an estuary varies according to one's location in the estuary, the daily tides, and the volume of fresh water flowing into the estuary. In estuaries, salinity levels are generally highest near the mouth of a river where the ocean water enters, and lowest upstream where freshwater flows in.
Explanation:
Answer:
a. more widespread in the body and affect distant targets.
Explanation:
Hormones are released into the blood by the dustless endocrine glands and the circulating blood delivers hormones to cells throughout the body. Therefore, hormones affect the distantly located cells throughout the body. For instance, growth hormone released by pituitary gland affects soft and hard tissues throughout the body.
On the other hand, the nervous system release neurotransmitters that affect the postsynaptic neuron or the muscle or gland cells present close to the site of their release. Target cells of neurotransmitters are more limited and include muscle (smooth, cardiac, and skeletal) cells, gland cells, and other neurons only.
<h2>Cannon -Bard theory</h2>
Explanation:
- Alone in the woods, Pedro hears a noise. He thinks he sees a bear coming toward him. His heart starts pounding and then, a moment later, he realizes how frightened he is. This sequence of events is BEST explained by the <u>Cannon-Bard t</u>heory of emotion.
According to Cannon-Bard theory, all the emotional expressions occur due to the stimulation of hypothalamic structures present in brain. This theory also states that feeling and physiological effects of an emotional stimuli occurs simultaneously.
Here, James thinks that a bear is coming, this is a stimulus. His heart starts pounding that is the physiological effect of the stimulus and the next moment he feels frightened which is a feeling.
So we conclude that in this case, the physiological effect and feeling of emotion occurred simultaneously. So these sequence of events is best explained by Cannon-Bard's theory.
Answer: Sea walnuts are marine invertebrates. They belong to the genus Mnemiopsis.
Explanation:
These animals have stinging tentacles like jelly fish and they often cast up or come to the sea shores where if they come in contact with humans can harm them by stinging.
The barrier if kept along the side of the sea shore and not allowing humans to reach to the shore can help in preventing the harm from these animals. The introduction of the predatory animals in the sea can also help in reducing their population.
The three benefits for removing the sea walnut:
1. The population of other species will increase as sea walnut is an invasive species.
2. The balance of the marine ecosystem can be maintained.
3. Humans can be protected from the harm caused by these animals.
