The respiratory system brings air into the lungs supplying the blood with oxygen. Oxygen is carried throughout the body to the organs and keeps the heart pumping and when the blood circulates back to the lungs the process starts over again.
Stimulus is something that causes a psychological response. It can be internal or external. The stimulus is the contact with the hot pan. It is an external stimulus. Sense organs, such as the sensory receptors in the skin are sensitive to external stimulus. The quickly pull of your hand is a reflex action.
The contact causes a nerve impulse that will travel to the spinal cord via the sensory neurons.<span>To respond to the stimulus of the reflex arc, the muscle needs to contract to pull the hand quickly away from the hot pan.</span>
Answer:
as I know
Explanation:
<em>Igneous rocks, which form from cooling magma or lava, and metamorphic rocks, which have been altered by heat and pressure, are unlikely to contain fossils. The “soft” tissues of an organism, such as skin, muscles, and internal organs are typically not preserved as fossils.</em>
An ecosystem is <span>a biological community of interacting organisms and their physical environment.</span>
Answer:
B) Nucleotides
Explanation:
The nucleotides sequence of DNA molecules determines the protein that will be produced. The mRNA molecules carry a copy of DNA to ribosome. the nucleotides consist of three parts- nitrogenous base, pentose sugar and a phospate group. There have more than six billion nucleotide pairs in a cell.