<span>Melanin helps protect the skin against effects of the sun such as skin cancers and premature aging. In African American skin, melanin provides a sun protection factor (SPF) equivalent to 13.4 compared to 3.4 in white skin and thus the former have lower incidences of skin disorders associated with exposure to the sun.</span>
The sympathetic nervous system releases hormones known as catecholamines which increase the heart rate.
<h3>What is a heart rate? </h3>
it is the number of contractions of the heart per minute.
<h3>What are catecholamines?</h3>
These are the neurotransmitters that have a catechol and a side chain that is an amine.
<h3>Which catecholamines are released by the sympathetic nervous system?</h3>
Epinephrine and norepinephrine are the catecholamines that are released by the sympathetic nervous system to increase the heart rate.
<h3>Where are these hormones released?</h3>
These hormones are released in the blood.
<h3>How does this hormone increase the heart rate?</h3>
- "These hormones are released at the neuromuscular junction of the cardiac nerves."
- "They shorten the repolarization period."
- This speeds up the rate of depolarization and contraction and thus the heart rate is increased.
To learn more about sympathetic nervous system, hormones and heart rate here,
brainly.com/question/1155838
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Answer:
<u>Inheriteted/Beneficial</u>
Explanation:
<em>First drop down</em>: "Sickle cell disease is passed on from parent to offspring."
<u>Inheriteted</u>
<em>Second drop down</em>
A increased resistance to a bad thing (malarial parasites) would be <u>Beneficial</u>
The answer to this is C- electromagnetic waves.
Hope that helps :)
Answer:
The correct answer is - Imprinting.
Explanation:
Imprinting is a behavior that includes both innate components and learning components and normally can not be irreversible. It is something that takes place at a specific sensitive period.
For instance, ducklings follow their mother is imprinting that is both innate and learned at a limited phase after birth during development. It can be visual or auditory or other ways that an animal can develop imprinting.
