Answer: Refractory period of the cardiac action potential
Explanation:
Unlike the skeletal muscle which can be reactivated before it reaches a contraction, cardiac muscle must wait before it is almost completely relaxed to be activated again (because of its long refractory period), so one cannot make an increase in strength of contraction with a high frequency of stimulations.
Answer:
d. increases their energy density and decreases nutrient density.
Correct; adding sugar to food increases energy density and decreases nutrient density.
Explanation:
Yes, Nicotine is very addictive, so like, if you take a ciggerate and start to smoke, the smoke enters your lungs, and nicotine is instantly absorbed into the blood and delivered into the brain, it takes effect sometimes as quickly as 10 seconds. Nicotine can change how the brain works or thinks, and can make the brain to crave more of it. Nicotine when it enters your brain realeses a thing called, dopimine which gives the person a good feeling. Dopamine is something in the nervous system to send messages to the brain cells, your body makes it, high levels of dopamine change our daily behaviors. So if nicotine releases or rises the dopamine, it can get you sick and addicted really easily in just 2 or 3 days of smoking, i will not consider smoking any tobaco.
Answer:
lymphocytes
Explanation:
Lymphocyte is a type of cell that is part of the body's immediate defense, acting against cancer cells and viral infections. Also, these cells are very important in wound healing. Slower healing of an injury is best explained by temporarily reduced lymphocyte production.
The concentration of these cells in the blood depends on the individual's physical condition: in cases of immunodeficiency, the concentration is low (lymphopenia); when there are infections or rejection of transplants, it increases (lymphocytosis). Lymphocyte count is a widely used test for monitoring diseases and infections such as those caused by HIV.