I would say both but the best would be the blood sugar
I am not 100% sure but i have an idea for the first box, In the circulatory system, blood is pumped into veins that carry the blood to tissues in your body. I really hope this helped you and was correct.
<span>They benefit from having the respiratory </span>system<span> give oxygen and take away carbon dioxide. Muscle </span>cells benefit<span> by having circulatory </span>system<span> bring them blood and oxygen. The heart pumps blood towards the arteries, arteries carry blood to the </span>cells<span>.</span>
Answer:
Lumen corresponds to the central opening of a vessel (option d).
Explanation:
From the biological point of view, lumen is the internal space of any structure or tubular organ, whose purpose is the conduction of substances through it.
In the case of blood vessels, the lumen is a central space covered by a simple epithelium, called the endothelium, which ensures the passage of blood in a fluid form.
The other options do not correspond to the answer:
<em> a. </em><u><em>Vessel that empties into the right atrium</em></u><em> is the vena cava</em>
<em> b. </em><u><em>Fibrous sac around the heart </em></u><em>is the pericardium.
</em>
<em> c. </em><u><em>Structure that keeps fluid moving forward</em></u><em>, it is a blood vessel.
</em>
<em> e. </em><u><em>Lower, pointed region of the heart</em></u><em>, corresponds to the cardiac apex.</em>
Here I can give you one = 1.Cutting one of your vascular veins which in turn can lead to permanent hand damage not being able to move/function your wrist muscles