Circulation

Circulation refers to the movement of fluids, such as blood, within the body. In the context of biology and physiology, circulation specifically refers to the flow of blood through the cardiovascular system, which includes the heart, blood vessels, and blood.

Functions of Circulation

The circulation of blood serves several important functions in the body:

Transportation: Blood carries oxygen, nutrients, hormones, and waste products to and from the cells in the body.
Regulation: Circulation helps maintain the body's internal environment by regulating temperature, pH, and fluid balance.
Protection: Blood contains white blood cells and antibodies that help defend the body against infections and diseases.

Components of Circulation

The circulatory system consists of several key components:

Heart: The muscular organ that pumps blood throughout the body.
Blood vessels: Arteries, veins, and capillaries that carry blood to and from the heart to various tissues and organs.
Blood: The fluid connective tissue that circulates through the cardiovascular system, carrying nutrients, oxygen, and waste products.

Circulation Process

The circulation of blood involves the following steps:

Heart contraction: The heart contracts to pump oxygen-rich blood to the body through the arteries.
Capillary exchange: Blood exchanges nutrients and waste products with the tissues at the capillary level.
Blood return: Deoxygenated blood returns to the heart through the veins, where it is then pumped to the lungs for oxygenation.
Lung exchange: In the lungs, blood picks up oxygen and releases carbon dioxide through the process of respiration.
Heart relaxation: The heart relaxes as oxygenated blood returns from the lungs and prepares for the next cycle of circulation.

Disorders and Diseases

Disruptions in circulation can lead to various disorders and diseases, including:

Hypertension: High blood pressure, which can strain the heart and blood vessels.
Coronary artery disease: Blockage of the blood vessels that supply the heart, leading to reduced blood flow to the heart muscle.
Stroke: Interruption of blood flow to the brain, often due to a blood clot or burst blood vessel.
Peripheral artery disease: Narrowing of the arteries in the limbs, leading to reduced blood flow and potential tissue damage.

Study Guide

Here are some key concepts to review when studying circulation:

Structure and function of the heart
Types of blood vessels and their roles
Composition and functions of blood
Cardiac cycle and circulation pathways
Regulation of blood pressure and flow
Common circulatory disorders and their causes

Understanding circulation is essential for comprehending various physiological processes and the maintenance of overall health and well-being.

◂Physics Worksheets and Study Guides High School. Thermodynamics

The resources above cover the following skills:

PHYSICAL SCIENCE (NGSS)

Matter and Its Interactions

Students who demonstrate understanding can:

Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.

Energy

Students who demonstrate understanding can:

Create a computational model to calculate the change in the energy of one component in a system when the change in energy of the other component(s) and energy flows in and out of the system are known.

Plan and conduct an investigation to provide evidence that the transfer of thermal energy when two components of different temperature are combined within a closed system results in a more uniform energy distribution among the components in the system (second law of thermodynamics).