Answer:
The semilunar valves prevent backflow of blood into the ventricles.
Explanation:
The semilunar valves are valves found at the junction between the left ventricle and the aorta and also between the right ventricle and the pulmonary artery. They are cup-like in shape and prevent blood from flowing back into the ventricles which are the pumping chambers.
There are two types of semilunar valves. The aortic semilunar valves and the pulmonary semilunar valves. They are made up of the endocardial and connective tissue.
The closure of the semilunar valves causes the second heart sound detected on the stethoscope.
Diseases that arise from the semilunar valves are caused by its stenosis which is the narrowing of the valves and regurgitation where the heart valves can no longer hold firm enough to prevent the backflow of blood.
Answer:
The five ideal shapes are: linear, trigonal planar, tetrahedral, trigonal bypramidal and octahedral.
They are found in the chromosomes
Answer:
This is a question of the ration surface-volume. It is more efficient a shape that has more surface than volume
Explanation:
Imagine the shape of a mouse and an elephant in a cold environment. Who will lose heat faster? The answer is the mouse, for its volume (which is small compared to the elephant), the surface for which it can lose heat is very large. In contrast, the surface for which the elephant can lose heat is very small for its volume.
The same happens with nutrients if you have a great volume and a small surface is more difficult to exchange them.
