Levels of Organization of Living Things

Vocabulary flashcards covering the biological hierarchy of living organisms (cells to organisms) and key homeostatic processes based on the lecture notes.

Cells

The basic building blocks of all living things, including plants, animals, and bacteria.

Tissues

Groups of similar cells that come together to perform a specific function.

Muscle tissue

A type of tissue that works to enable movement, such as brushing your teeth or lifting a backpack.

Nervous tissue

A type of tissue that transmits signals to the brain, such as sensing when it is cold outside.

Organs

Body structures formed by tissues with the same function working together to carry out specialized jobs.

Stomach

An organ whose specific job is to break down ingested food so the body can obtain the energy it needs.

Heart

An organ that pumps blood carrying oxygen throughout the body.

Organ system

A group of organs with similar jobs that work together; the human body contains 11 different systems.

Skeletal system

An organ system composed of all the bones in the body that keeps an organism standing or sitting tall.

Digestive system

An organ system comprising various organs, including the stomach, that works to break down food and absorb energy.

Homeostasis

The process by which living organisms keep internal conditions and temperature the same.

Shivering

A homeostatic response to cold where muscles twitch and move to generate warmth for cells and tissues.

Sweating

A homeostatic response to heat where water on the skin helps cool off cells and tissues.

Panting

A cooling behavior in animals like dogs where excess heat is released from the tongue while drawing in cool air.

Involuntary

Describing actions or homeostatic responses that happen automatically without conscious thought.

Organism

A complete living individual formed by multiple organ systems functioning together.