The Systems of the Human Body

What are the Human Body Systems We Have Studied So Far?

Skeletal Muscular Digestive Respiratory Now… Circulatory Nervous Immune

The Circulatory System

Is Blood Blue? Blood is a bright red in its oxygenated form (i.e.,

leaving the lungs), when hemoglobin is bound to oxygen to form oxyhemoglobin. It's a dark red in its deoxygenated form (i.e., returning to the lungs), when hemoglobin is bound to carbon dioxide to form carboxyhemoglobin.

Veins appear blue because light, penetrating the skin, is absorbed and reflected back to the eye.

Functions of the Circulatory System (Blood)

1. Carries oxygen (O₂) from the lungs to all of your body cells (RBC’s)

2. Helps the body get rid of waste products (CO ₂)

3. Transports nutrients to cells4. Fights infections & heals wounds (WBC’s

& Platelets)

The Composition of Blood The Plasma (Fluid)

makes up 55% of the blood volume.

The Solids (Cells) make up 45% of the blood volume.

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Blood Composition

Plasma Solids

Composition of Blood

97% Water Other 3% -Antibodies and

Proteins - Nutrients and

Wastes

Red Blood Cells -Carry oxygen -Contain Hemoglobin White Blood Cells -Attack bacteria &

other invaders Platelets -Control the blood

clotting process

Plasma Blood Solids

3 Types of Blood Vessels1. Arteries (Away)

- The Aorta is the largest artery2. Veins

- The Vena Cava is the largest vein3. Capillaries

- Very Small - Site of O₂ & CO₂ exchange - Connect Veins & Arteries

Lungs

Body cells

Our circulatory system is a double circulatory system. This means it has two parts parts.

the right side of the system

deals with deoxygenated

blood.

the left side of the system deals with

oxygenated blood.

Pathway of Blood

Structures of The Heart

Left Ventricle

Left AtriumRight Atrium

Right Ventricle

valve

Vein from Lungs

Artery to Head and BodyArtery to Lungs

Vein from Head and Body

valve

Types of Circulation

Coronary Within the heart

Pulmonary Flow of blood from the heart to the lungs

Systemic Blood moving to other parts of the body

Pathway of blood

Blood Circulation Animation https://

www.youtube.com/watch?v=mH0QTWzU-xI

Where is pressure the greatest? Veins or Arteries? Why?

Blood Pressure Blood pressure is the force of the

blood pushing against the walls of the arteries.

Blood Pressure There are two kinds of numbers

that make up a blood pressure reading. These numbers are written like a fraction -- the top number refers to systolic blood pressure (while the heart is beating), and the bottom number measures the diastolic blood pressure (while the heart is at rest).

Normal numbers for blood pressure range from 90/60 to 120/80.

Cardiovascular Disease Leading cause of death

Atherosclerosis: fatty deposits on artery walls

Hypertension: High blood pressure

Credits Graphics courtesy of Crystalcafe.com &

The Franklin Institute online.