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
Cephalocaudal pattern of motor development
The correct answer is 9 proteins form each of the 20 facets of this virus. A capsid is the protein shell that surrounds a virus. A capsomere is the subunit of the capsid. Depending on the virus, capsomeres arrange in many different shapes to form the capsid. The yellow mottle virus has 20 facets, this means that it has an icosahedral capsid. Since it contains 180 identical capsomeres, we can conclude that 9 proteins form each facet.
The correct option is (A) in biomes at different latitudes.
When climbing a mountain, we can observe transitions in biological communities that are analogous to the changes in biomes at different latitudes.
<h3>
What is biome?</h3>
- A naturally existing species community that is influenced by a region's climate and latitude is referred to as a "biome."
- A place where two biological communities come together and merge is known as an ecotone. It could be small or large, local (the area between a field and a forest), or regional (the transition between forest and grassland ecosystems).
- As you ascend a mountain, different sections experience varying amounts of sunlight and warmth. People see differences in the biological community as an organism ascends a mountain because different latitudes are present.
Learn more about the biome with the help of the given link:
brainly.com/question/18601179
#SPJ4
Saturated fat has only single bonds between the carbon atoms