What is biology?

Biology is the study of living things (organisms).

An organism is any living thing.

All living things share certain characteristics.

Characteristics of Organisms

Characteristics of Living Things

1. They are made of one or more cells.

Unicellular (one cell)

- ex. Bacteria

Multicellular (many cells)

- ex. Protists, fungi, plants, Animals

2. They need energy to survive.

Autotrophs get energy from the sun to:

(make glucose by a process called photosynthesis).

Then they convert glucose into ATP in cellular respiration.

Heterotrophs get energy by consuming nutrients from their environment. Then they take glucose and make ATP by a process called cellular respiration.

3. They respond to stimuli in their environment.

Stimuli are factors in the environment that living things react to such as light, temperature, sound, etc.

4. All living things reproduce.

Sexual reproduction occurs when two sex cells join (sperm and egg). Meiosis is the cell division used to make an egg, sperm, or spore.

Asexual reproduction occurs when one parent cell divides.

5. They grow and develop.

Each cell divides to make new cells. Cell division results in growth by mitosis.

To develop you go through a series of changes in form and function. A caterpillar develops into a butterfly.

6. They maintain homeostasis.

Homeostasis is maintaining a relatively stable internal environment (within a certain range). “Balance”

- ex. human body temperature is approximately

98.6 degrees F.

7. They have adaptations that

help them evolve over time.Evolution is a gradual change in a population of organisms over time.

Individuals DO NOT evolve.

8. They have a universal genetic code.

All living things have DNA.

DNA passes on genetic information from one generation to the next.

DNA is deoxyribonucleic acid.

Which of the life characteristics is the one that only living things

possess?

How do I remember all of these?

S – charged….. Think about it…