Download Biology as a Science

Biology as a Science
Characteristics of Living Things
All Living Things:
•
•
•
•
•
Are made up of 1 or more cells
Reproduce
Grow and develop
Obtain and use energy
Respond to their environment
Cells- smallest unit that carries on life
• Unicellular- 1 celled
• Multicellular- many
celled
Reproduction- produce new organisms
of the same type
• Sexual - requires 2 cells to unite to form first
cell of new organism
• Asexual – requires 1 cell to form a new
organism
Growth and Development
Birth
Development
Aging
Death
Energy
• Anabolism- any process in a living thing that
involves putting together complex substances
from simpler substances
Ex: photosynthesis: sugar is
synthesized using the sun’s energy
Energy
• Catabolism- the breakdown of complex
substances to simpler substances, usually
resulting in a release of energy
Ex: Digestion of foods
Energy
• Metabolism- the total sum of all chemical
reactions
• Anabolism + catabolism = metabolism
Response
• An organism must be able to respond to the
environment.
– a stimulus causes a response in an organism
• Homeostasis- refers to an organism’s ability
to maintain constant or stable conditions that
are necessary for life.
– homeo = same
stasis = state (condition)