Biological soil crusts<span> are communities of living organisms on the </span>soil<span> surface in arid and semi-arid ecosystems. They are found throughout the world with varying species composition and cover depending on topography, </span>soil<span> characteristics, climate, plant community, microhabitats, and disturbance regimes.</span>
Certain fossils, called index fossils, help geologists match rock layers. To be useful as an index fossil, a fossil must be widely distributed and represent a type of organism that existed for a brief time period. Index fossils are useful because they tell the relative ages of the rock layers in which they occur.
Endocrine system is involved in this
Answer:
1A - Respiratory = trachea, lungs... however both arteries and veins move oxygen around the body, and are therefore valid answers
1B - Skeletal = bones
1C - Muscular = muscles
1D - Digestive = stomach, large/small intestine
1E - Circulatory = heart, veins and arteries
2. Cellular respiration is the conversion of sugar into energy the cell uses to function via various chemical reactions. Digestion is an example of this. Stomach acid breaks down food into sugars that cells break down further into energy to keep you alive
3. Bones contain bone marrow deep inside of them which is responsible for the creation of red blood cells. Your lungs can move air all they want but would be useless without red blood cells to take the oxygen to cells and take the CO2 away from them.
Answer is that the cells exist inside the body
Explanation:
i went to science class 1 time in freshmen year