Answer:
Answer is Sinoatrial node, SA.
Explanation:
The sinoatrial node, SA, is known to be a group of cells which are found at the top of the heart.
The electrical signal that is initiated by the sinoatrial node bring about or stimulates the atria and then the ventricle of the heart.
It should be noted that, the sinoatrial node are regarded as the pacemaker cells.
Answer:
b) from a region of high pressure to a region of low pressure
Explanation:
Blood flow is measured in blood volume per unit time. It is the movement of blood through an organ, tissue or vessel. It is initiated when ventricles in heart contract leading to its ejection at high pressure. Major arteries receive this blood and they further transport it at high pressure to smaller arteries, arterioles and capillaries. Hence arteries have thick walls to withstand this pressure. The pressure decreases when blood reaches to veins hence their walls are not that thick. Hence, blood flows from a region of high pressure to a region of low pressure.
answer: Neuro filaments
explanation:
Neurofilaments (NF) are intermediate filaments found in the cytoplasm of neurons. Together with microtubules and microfilaments, they form the neuronalcytoskeleton. They are believed to function primarily to provide structural support for axons and to regulate axon diameter, which influences nerve conduction velocity.
Its often referred to as the colon
