Human Body Organization and Systems

What is the most basic level of organization in the human body?

Which directional term refers to a location closer to the midline of the body?

What is the term for the region within the body that contains the heart and lungs?

Which body region includes the arm, forearm, and hand?

What is the term for the group of organs that work together to bring oxygen into the body?

Which body system produces hormones?

What is the primary function of the circulatory system?

Which of the following is responsible for pumping blood throughout the body?

What is the term for the circulation of blood between the heart and lungs?

Which of the following blood vessels carries deoxygenated blood back to the heart?

What is the highest pressure in the arteries, which occurs when the heart beats?

What is the smallest unit of the circulatory system where oxygen and nutrients are exchanged with cells?

Organization of the Human Body

The human body is composed of several levels of organization:
- Chemical level: atoms, molecules
- Cellular level: cells, tissues
- Tissue level: groups of similar cells
- Organ level: structures composed of two or more types of tissues
- Organ system level: groups of organs working together
- Organismal level: the entire human body

Directional Terms

Used to describe the location of body parts in relation to each other:
- Anterior (front)
- Posterior (back)
- Superior (above)
- Inferior (below)
- Medial (toward the midline)
- Lateral (away from the midline)
- Proximal (closer to the trunk)
- Distal (farther from the trunk)

Body Cavities

Regions within the body that contain internal organs:
- Cranial cavity: contains the brain
- Vertebral canal: contains the spinal cord
- Thoracic cavity: contains the heart and lungs
- Abdominal cavity: contains the digestive organs
- Pelvic cavity: contains the reproductive organs

Body Regions

Divisions of the body:
- Head: skull, face, and brain
- Neck: connects the head to the body
- Trunk: thorax and abdomen
- Upper limb: arm, forearm, and hand
- Lower limb: thigh, leg, and foot

Body Systems

Groups of organs that work together to perform specific functions:
- Nervous system: controls body functions
- Circulatory system: transports oxygen and nutrients
- Respiratory system: brings oxygen into the body
- Digestive system: breaks down food for energy
- Endocrine system: produces hormones
- Integumentary system: protects the body
- Muscular system: moves the body
- Skeletal system: supports the body
- Urinary system: removes waste
- Reproductive system: produces sex cells

Explore the different levels of organization in the human body, from chemical to organismal level. Learn about directional terms, body cavities, body regions, and body systems. Test your knowledge of human anatomy!