Download Characteristics of Living Things

Lesson Overview
Studying Life
Lesson Overview
1.3 Studying Life
Lesson Overview
Studying Life
Characteristics of Living Things
Biology is the study of life. But what is life?
What characteristics do all living things share?
Living things are all
- made up of basic units called cells
- based on a universal genetic code
- obtain and use materials and energy
- grow and develop (change)
- reproduce
- respond to their environment
- maintain a stable internal environment (homeostasis)
- evolve.
Lesson Overview
Studying Life
Characteristics of Living Things
#1 - Living things are made up of one or more cells.
unicellular = made of one cell (bacteria)
multicellular = made of many cells (us!)
- Cells can grow, respond to their surroundings, and
reproduce.
Lesson Overview
Studying Life
Characteristics of Living Things
#2 - Based on a universal genetic code.
- All organisms store the complex info they need in a genetic
code written in DNA.
- DNA is copied/passed from parent to offspring and is almost
identical in every organism on Earth.
Lesson Overview
Studying Life
Characteristics of Living Things
#3 - Living things grow and develop.
- A single fertilized egg divides again and again.
- As these cells divide and differentiate = they begin to look
different from one another and to perform different functions.
Lesson Overview
Studying Life
Characteristics of Living Things
#4 - Living things respond to their environment.
- A stimulus is a signal to which an organism responds.
- For example, some plants can produce unsavory chemicals to
ward off caterpillars that feed on their leaves.
Lesson Overview
Studying Life
Characteristics of Living Things
#5 - Living things reproduce.
- Most plants and animals engage in sexual reproduction, cells
from two parents (sperm + egg) unite to form the first cell of a
new organism.
- Asexual reproduction is when one cell splits, or divides, into
two new identical cells.
Lesson Overview
Studying Life
Characteristics of Living Things
#6 - Living things maintain a stable internal environment.
- All living organisms maintain homeostasis.
- For example, even though it’s cold outside, your internal
temperature remains close to 98.6ºF.
Lesson Overview
Studying Life
Characteristics of Living Things
#7 - Living things obtain and use energy.
- The sum of all chemical reactions in your body =
metabolism.
Lesson Overview
Studying Life
Characteristics of Living Things
#8 - Over generations, groups of organisms evolve, or change over
time.