Answer:
Venous return (VR) is the flow of blood back to the heart.
Venous return to the right atrium is the most important factor determining cardiac output, provided both ventricles and the pulmonary circulation are normal.
Explanation:
Venous return refers to the flow of blood from the periphery back to the right atrium, and except for periods of a few seconds, it is equal to cardiac output.
Venous return is facilitated by a number of factors, including inspiration, increased total blood volume, increased venomotor tone, the cardiac suction effect, the presence of venous valves and the skeletal muscle pump.
Contraction of the skeletal muscles surrounding veins increases the pressure within the veins, pushing open the proximal valve and forcing blood toward the heart. For example, when calf muscles contract during exercise, blood is forced toward the heart, thus increasing venous return.
Learn more about venous force here:-
brainly.com/question/11621104
#SPJ1
It is b density ! Good luck sorry if late
Answer:The functions of hair include protection, regulation of body temperature, and facilitation of evaporation of perspiration; hairs also act as sense organs. Hairs develop in the fetus as epidermal downgrowths that invade the underlying dermis.
Explanation:that's why people grow hair
The pollen grains contain sperm which will fertilize the egg and create a seed to sprout the next generation of plants. The main male part is the stamen. It is divided into two parts: the anther and the filament. The anther produces the pollen grains that contain the sperm needed for fertilization.
