Chapter 5 Circulatory System Flashcards Preview

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Flashcards in Chapter 5 Circulatory System Deck (11):
1

What is the cardiovascular system?

Includes the heart and blood vessels

Brings nutrients to cells and helps get rid of waste

Blood is refreshed in the lung, kidneys, intestines, and liver

2

What are the functions of cardiovascular system?

1. Generate blood pressure
2. Transport blood
3. Exchange of nutrients and wastes at the capillaries
4. Regulate blood flow as needed

3

What is the main pathway of blood in the body?

Heart --> arteries --> arterioles --> capillaries --> venules --> veins --> back to the heart

4

Arteries and arterioles

Carry blood away from the heart

Arterioles are small arteries that regulate blood pressure

Composed of 3 layers: Thin inner epithelium, thick smooth muscle layer, outer connective tissue

5

Capillaries

Microscopic vessels between arterioles and venules

Made of one layer of epithelial tissue

Exchange of oxygen occurs at capillary beds

Combined large surface area

6

Exchange at the capillary beds is primarily a result of

Osmotic pressure, blood pressure, and diffusion

7

In the arterial end of capillary:

Arterial blood is bright red, nutrient rich
BP (30 mmHg) > osmotic pressure (21 mmHg)
Contains water and small molecules that form tissue fluid

8

In the midsection capillary:

Concentration of oxygen and nutrients is much higher here than at the arterial end; low concentrations of carbon dioxide

9

In the Venous end of capillary:

BP = 15 mmHg (less than osmotic pressure)
Size of capillary is largest at venous end
Water enters capillaries, bringing along waste

10

Metarteriole

capillary that connects veins to arterioles

11

Sphincter

Function: They constrict to prevent blood from flowing through certain capillaries in the body; this is because the human body does not contain enough blood to be everywhere at once, so this controls where the blood flows and where it doesn't