Lecture 12

Question 1

What is circulation within animal bodies?

Answer 1

It is the pressure -driven bulk flor of a body fluid this is through a system of vessels and other things that brings fluids throughout the body. It manages the transport of all kinds of fluids and such like O2, Co2, Hormones, waste products and heat

Question 2

What is a heart?

Answer 2

It is a discrete localized pumping structure. It can range from a single chamber to multiple chambers. The muscle of the heart is called the myocardium

Question 3

How does the human heart function?

Answer 3

1. Oxygenated blood from the lungs travels to
   the heart via pulmonary veins and enters the
   left atrium
2. Blood flows through the left atrioventricular
   valve to enter the left ventricle
3. Oxygenated blood is then pumped through
   the aortic valve into the systemic aorta
4. Partially deoxygenated blood returns via the
   superior vena cava and into the right atrium
5. Blood flows through the right atrioventricular
   valve and enters the right ventricle
6. Deoxygenated blood is then pumped through
   the pulmonary valve and into the pulmonary
   trunk

Question 4

how is oxygen delivered into the myocardium?

Answer 4

so for starters the myocardium is compact this means that blood traveling through cannot reach much of this instead there are things like the coronary circulation which are small arteries/ veins that follow the miocardium, allowing for o2 entry and co2 exit.

Question 5

What are the different heart signals?

Answer 5

There are myogenic hearts which are electrical impulse to contract muscle cells

Neurogenic hearts - electrical impulse that contracts in neurons

Question 6

What are some pressure principles that need to be taken into account when analyzing resistance and flow?

Answer 6

Perfusion, which is the forced flow of blood in vessels, also there ate things like fluid column effects that exerts hydrostatic pressure which increases the hight of something to be tested.

To determine blood flow taking into account resistance, you subtract p in from p out. and this rate is proportional to the lumens radius

Question 7

Now looking at animals what kind of heart do mammals and birds have?

Answer 7

4 chambered hearts

Question 8

What does circulation in mammals and birds look like?

Answer 8

Blood vessels at various points in the systemic vascular system differ anatomically and functionally in important ways

• In vertebrates, all vessels are lined on the inside with a single layered epithelium (vascular endothelium)

Arteries - thick walls with smooth and elastic muscle and connective tissues, they dampen things and reservoir pressure

there are also microcirculatory beds, that consist of vessels, arterioles, capillaries and venules