4 Structural and Functional Organization of the Human Body

Chemical Level

• simplest level of the structural ladder and basis unit of organism

• includes how different atoms (hydrogen and carbon) interact to form molecules

• DNA & Glucose

Cell

basic structural and functional and smallest unit of life

Cell Level

• perform all activities necessary to maintain life (metabolism, assimilation, digestion, excretion, reproduction)

• basic structural and functional units of an organism that are composed of chemicals

Tissue Level

Group of cells that perform one or more functions

Four

How many types of tissues are there?

Epithelial Tissue

• covers body surface

• lines hollow organs and cavities and forms glands

Connective Tissue

connects, supports, and protects body organs while distributing blood vessels to other tissue

Muscle Tissue

contractss to make body part move and generates heat

Nervous Tissues

carries information through nerve impulses

Hemopoietic

blood cells for distribution of substances and protection from infection

Organ Level

• composed of two or more tissues that perform the same function

• stomach, heart, brain, skin, bones, lungs

Peristalsis

movement of gastrointestinal organs

Organ System Level

• consists of related organs working together to sustain a specific function

• digestive system

Organism Level

any living thing considered as a whole whether composed of one cell such as bacterium, or of trillion of cells, such as human