CIRCULATORY AND RESPIRATORY

BLOOD FUNCTION

• transports nutrients, O2, CO2, & waste

• defends the body against disease

COMPONENTS OF BLOOD

1. PLASMA: liquid medium

• made of 90% water, sugar, salts, amino acids, vitamins, minerals

COMPONENTS OF BLOOD

2. RED BLOOD CELLS (erythrocytes): transport CO2 and O2 gas

• made of iron-containing hemoglobin (O2 binds here)

• lack of nucleus leaves space to transport materials

COMPONENTS OF BLOOD

3. WHITE BLOOD CELLS (leukocytes): defend against pathogens

COMPONENTS OF BLOOD

4. PLATELETS: form blood clots

CIRCULATORY SYSTEM

Function• Moves nutrients and waste throughout the body

STRUCTURES

1. Heart: muscular organ that pumps blood to all parts of the body.

• Divided into right side and left side by septum • Each side has an upper section (atrium) and lower

section (ventricle).

STRUCTURES, CONT.2. Vessels: smooth muscle surrounded by connective tissue

STRUCTURES, CONT.2. Vessels: smooth muscle surrounded by connective tissue

• arteries – carries blood AWAY from the heart

• veins –carries blood to the heart

STRUCTURES, CONT.2. Vessels: smooth muscle surrounded by connective tissue

• arteries – carries blood AWAY from the heart

• veins –carries blood to the heart

• capillaries –narrow blood vessels that pass blood in single file. Gas exchange occurs here.

MOVEMENT OF BLOOD

Two Circuits (Pathways)1. Pulmonary (deoxygenated)

• right side of heart sends blood to the lungs for gas exchange

MOVEMENT OF BLOOD

Two Circuits (Pathways)1. Pulmonary (deoxygenated)

• right side of heart sends blood to the lungs for gas exchange

2. Systemic Circuit (oxygenated)• left side of heart sends blood to the body to

deliver oxygen and pick up waste

RESPIRATORY SYSTEMExternal Function

• Exchange of gases between atmosphere and blood

Pathway• mouth/nose pharynx epiglottis trachea bronchi lungs

MECHANISM

Large skeletal muscle (diaphragm) contracts pulling thoracic cavity down causing the lungs to fill with air

INTERNAL FUNCTION

• Exchange of gases between blood and other body cells

• Gases diffuse across due to concentration gradients (high to low)