The Needs & Characteristics of Living Things

This flashcard set covers the essential requirements for life and the eight core characteristics shared by all living organisms, including biological terms and processes such as homeostasis and natural selection.

Organisms

Any living thing.

Basic Needs of All Organisms

Water, nutrients, space to live, and air ($O_2$ or $CO_2$).

Water (Biological Function)

Helps organisms carry out cellular activity, including DNA replication, cell division, protein synthesis, and the transport of nutrients and wastes.

Nutrients

Materials that provide organisms with what they need to grow, including carbohydrates, proteins, fats, vitamins, minerals, and water.

Autotrophs (Producers)

Organisms like plants and some bacteria that produce their own food for energy through photosynthesis or chemosynthesis.

Heterotrophs (Consumers)

Organisms that eat other organisms to obtain proteins and energy, categorized as carnivores, herbivores, or omnivores.

Phosphorus

A nutrient that provides building blocks for growth and helps plants develop roots, flowers, and healthy cells.

Space to Live

A requirement that provides organisms with a place to get food, water, and shelter; organisms often compete for this resource.

Air ($CO_2$ and $O_2$)

Plants need $CO_2$ for photosynthesis, while both plants and animals need $O_2$ for cellular respiration.

Cool Hippos Eat Really Tasty Green Red Cherries

A mnemonic for the 8 characteristics of life: Cells, Homeostasis, Energy, Reproduce, Traits, Grow, Respond, and Change.

Unicellular

Simple organisms made of a single cell, such as bacteria.

Multicellular

Complex organisms made of many cells, such as animals and plants.

Homeostasis

The ability to maintain internal conditions in response to environmental changes, such as sweating in hot conditions or shivering in cold conditions.

ATP (Adenosine Triphosphate)

The cell's energy currency that powers daily functions and the repair or replacement of damaged cells.

Sexual Reproduction

A process involving two parents to produce offspring with different genes.

Asexual Reproduction

A process involving a single parent to produce offspring that is identical to the parent, known as a clone.

DNA (Deoxyribonucleic acid)

The molecule where genes are found and through which traits are passed to offspring.

Growth

The process by which organisms get larger through cells increasing in number or size.

Stimulus

Any activity that brings about a response; can be internal (like hunger or thirst) or external (like light or sound).

Natural Selection

The process where traits best suited for the environment survive to be passed on to offspring, causing a species to change over time.

Evolution (Population Scale)

The concept that individuals cannot evolve; only populations can change over time.