#11 The atria contract, forcing deoxygenated blood from the right atrium, through the...
-
Upload
noel-mccormick -
Category
Documents
-
view
219 -
download
0
description
Transcript of #11 The atria contract, forcing deoxygenated blood from the right atrium, through the...
![Page 1: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/1.jpg)
![Page 2: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/2.jpg)
#11
• The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle.
• #4 occurs simultaneously.
![Page 3: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/3.jpg)
#1
• The right ventricle contracts, slamming shut the atrio-ventricular valve, and forcing blood out of the heart to through the pulmonary artery.
• Occurs simultaneously with #5.
![Page 4: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/4.jpg)
# 2• Blood flows through
the pulmonary artery (arteries) to both the right and left lungs.
• As the ventricle relaxes, the semi-lunar valve slams shut, producing the second heart sound.
• Occurs simultaneously with #6.
![Page 5: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/5.jpg)
#3• In the lungs, blood
releases CO2 and absorbs O2 from the air.
• This occurs by simple diffusion (although there are some cool details we’ll talk about later).
• Blood returns to the heart through the pulmonary veins to the left atrium.
![Page 6: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/6.jpg)
#4
• Blood returns from the lungs to the left atrium.
• The left atrium contracts, which forces blood into the left ventricle (occurs simultaneously with #11).
![Page 7: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/7.jpg)
#5
• The left ventricle contracts, slamming shut the atrio-ventricular valve and forcing blood out of the heart through the aorta.
• Occurs simultaneously with #1.
![Page 8: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/8.jpg)
#6• Blood moves out of
the heart through the aorta.
• As the ventricle relaxes, high back-pressure in the aorta slams shut the semi-lunar valve, producing the second heart sound.
• Occurs simultaneously with #2.
![Page 9: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/9.jpg)
#7 & 8
• Blood is carried by arteries, and arterioles to the head, forelimbs, abdominal organs, and hind limbs.
• There arterioles split into much smaller vessels called capillaries, where cells can exchange nutrients and waste products.
![Page 10: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/10.jpg)
#9 & 10
• Capillaries reform into venules and then veins, and finally to either the inferior vena cava or the superior vena cava.
• This blood re-enters the heart at the right atrium, and the cycle repeats.
![Page 11: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/11.jpg)
![Page 12: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/12.jpg)
Arteries• Arteries carry high
pressure blood away from the heart.
• They have thick, strong layers of muscle and connective tissue surrounding them, which allows them to carry high pressures.
![Page 13: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/13.jpg)
Capillaries• Capillaries are specialized for material exchange.• They are very tiny, and allow a single file line of blood
cells to pass.• They are “fenestrated” to allow fluids to leak out and
bathe the surrounding tissue cells. • Materials enter and leave blood by diffusion and osmosis.
![Page 14: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/14.jpg)
Veins • Veins carry low pressure blood back to the heart.
• Veins have thinner layers of muscle and connective tissue so they remain flexible.
• They also have one-way valves to prevent low pressure blood from flowing backwards due to gravity or inactivity.
![Page 15: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/15.jpg)
Atherosclerosis
• Is the build up of fats and cholesterol along the inner wall of arteries.
• This narrows the lumen of the arteries and restricts blood flow.
![Page 16: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/16.jpg)
• Atherosclerosis occurs when there is damage to the inner wall of the arteries - caused by high blood pressure and/or chemicals in the blood.
• This results in the release of growth factors which cause the muscle layer around the wall to thicken, and the wall to be more permeable to fats and cholesterol.
![Page 17: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/17.jpg)
• LDL (Low density lipoproteins) deposit cholesterol along the walls of the arteries.
• These deposits eventually crystalize and harden (atherosclerosis is also called “hardening of the arteries”).
• The build-up reduces blood flow and causes turbulence which can lead to Thrombosis or the formation of blood clots.
• Together, atherosclerosis and thrombosis can cause CHD, or coronary heart disease.
![Page 18: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/18.jpg)
• Some of the first arteries to branch from the aorta are the coronary arteries.
• These arteries supply the heart muscle itself with the blood and oxygen needed to keep pumping.– See model
![Page 19: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/19.jpg)
• If atherosclerosis and thrombosis (CHD) lead to a blockage of the coronary arteries, the cells of the heart are starved of oxygen, and lose the ability to contract.
• This is a heart attack, or a myocardial infarction.
• If arteries in the brain become blocked, a stroke results.
![Page 20: #11 The atria contract, forcing deoxygenated blood from the right atrium, through the atrio-ventricular valve into the right ventricle. #4 occurs simultaneously.](https://reader035.fdocuments.net/reader035/viewer/2022062504/5a4d1b157f8b9ab0599912cc/html5/thumbnails/20.jpg)
Risk factors for CHD
• Genetics• Age• Gender• Diet/obesity• Activity level• Lifestyle (smoking, etc.)