They are calle trace fossils.
Answer:
because they cannot reproduce by themselves without a host viruses are not considered living. Nor do viruses have cells they're very small, much smaller than the cells of living things and are basically just packages of nucleic acid and protein.
Explanation:
Hope this helped Mark BRAINLIEST!!!
Answer:
Active transport; Passive transport; Passive transport
Explanation:
When concentration of a substance is different on either side of a semi-permeable membrane, the movement of this substance can occur by active or passive transport. Active transport occurs when the substance is moved from the region of its lower concentration to that of its higher concentration. This type of movement uses the energy to move the substance. Since the glucose concentration is higher in the epithelial cells than in the food, it will enter into the cells by the process of active transport.
The passive movement of substances is driven by concentration gradient. The glucose concentration is lower in extracellular space than epithelial cells, so glucose will be transported into the extracellular space by passive movement.
Likewise, a higher concentration of glucose in extracellular space than blood will move it passively into the bloodstream.
Is there more to this question?
<h2>Answer </h2>
Blood is carried by a Superior and Inferior Vena Cava toward the heart
<u>Explanation </u>
Most veins transport deoxygenated blood through the tissues returning to the heart except pulmonary and umbilical vein that transfers oxygenated blood to the heart whereas arteries carry blood away from the blood. The main blood vessels aorta, superior vena cava, and inferior vena cava carry deoxygenated away from the heart to lungs while pulmonary veins carry the oxygenated that is oxygen-rich blood from lungs to the heart.