<span>Collin often experiences a "runner's high" during his daily three-mile run. this is most likely produced by endorphins.
Endorphins are related to a group of hormones which are secreted within the brain and the nervous system, it is like morphine chemicals which are produced. It is mostly produced when you exercise a lot, run high or stress etc.</span>
Answer:
D. By diffusion across a capillary wall
Explanation:
D is the best answer because gas exchange takes place in our lungs. Our lungs have alveoli which have a network of tiny blood vessels called capillaries, here the O2 diffuses the capillary wall to enter the bloodstream, and similarly CO2 diffuses out and we exhale it our from our lungs.
The best summary of the process of natural selection will be provided bythe option D that is genes are always passed from parent to offspring . Hence , out four inheritance is one of the option in the given question that is gene are passed from parent to offspring .
Answer:
skeletal, cardiac, and smooth
Answer:
Troposphere, stratosphere, mesosphere, thermosphere
this is the layers from space into earth