Life Activities:
Nutrition - obtaining materials from
the environment and changing them into useful forms.
-
This includes ingestion(taking
in food) and digestion(breaking down food) for most animals.
Transport - movement of materials into
and out of organisms, throughout organisms, and into and out of the cells.
Synthesis - building up of larger molecules
like proteins and lipids from smaller molecules.
-
Plants synthesize sugar from carbon dioxide in the process of photosynthesis.
Assimilation - "You are what you eat."
The incorporation of materials into the body. This leads of growth.
Growth - increase in size. In
multicellular organisms growth includes both increase in cell size and
number.
In unicellular organisms
growth includes only increase in cell size.
Cellular Respiration - the removal
of energy from food molecules by breaking it down (catabolism).
-
aerobic respiration - uses oxygen to remove 18 times the energy that anaerobic
respiration can remove.
-
anaerobic respiration - no oxygen
Regulation - the maintenance of homeostasis
(steady internal environment).
-
In animals regulation is controlled mostly by the nervous and endocrine
(hormones) systems.
Reproduction - the creation of new individual
organisms.
-
asexual reproduction - one parent produces new individual identical to
itself.
-
sexual reproduction - two parents produce new individuals that have a mix
of the parents traits.
Metabolism - all the chemical reactions that
occur in the body of the organism.
-
anabolism - building up larger molecules from smaller ones. (synthesis)
-
catabolism - breaking down larger molecules into smaller ones. (digestion/hydrolysis/cellular
respiration)
Excretion - Removal of cellular waste from the
organism. In animals the major excretory organs are the lungs, skin,
and urinary system(kidneys
and bladder). The large intestine is involved somewhat, but its function
is more accurately
describe as elimination.
Most of the material that passes through the large intestine is not waste
from chemical reactions,
rather it consists of unused
food material.