Transcript What are the characteristics of living things?

Aim: What are the characteristics
of living things?
Topic: Conditions for life
What is BIOLOGY?
- the study of life.
What is an ORGANISM?
- any living thing.
What is an Environment?
- the surroundings of an organism which
affects how it lives.
What do all organisms need to survive?
CONDITIONS/FACTORS FOR LIFE:
1. SOURCE OF ENERGY
- needed for life processes.
- light, FOOD
**The SUN is the origin of almost all the
energy available to all living things.
2. WATER
- water makes up more than 65% of all
organisms.
- it dissolves & carries materials
throughout an org.
- many chemical reactions take place in
water.
- helps keep an organisms temperature
stable.
3.
-
GASES
found in the environment.
needed to perform life processes.
oxygen (O2), carbon dioxide (CO2) &
nitrogen (N).
4. PROPER TEMPERATURE
- needed to maintain “homeostasis” or
“dynamic equilibrium” which means to
have a constant, stable internal
environment.
5. PROPER HABITAT
- a place to live and find all the other
factors needed for to carry out the life
processes.
What are the life processes?
- processes that all living things must do
in order to survive. THEY ARE:
1. METABOLISM
2. RESPONSE
3. GROWTH
4. MOVEMENT
5. REPRODUCTION
What is METABOLISM??
1. Metabolism = total of all the
chemical activities that occur in a
living thing involving energy
usage.
e.g. Building substances.
Breaking down substances.
- in order for these chemical
reactions to take place, organisms
must take in food for energy.
What are the parts of METABOLISM?
Nutrition:
1. INGESTION
-taking in food.
2. DIGESTION
-breaking down food.
3. EXCRETION
- removal of wastes produced by an organism
4. RESPIRATION
- process by which an organism changes
some of the energy stored in food into a more
usable form (ATP). CO2 is produced as a
waste product.
Synthesis:
**The reverse of respiration is
PHOTOSYNTHESIS – the process by
which plants take in CO2, H2O, sunlight and
make food.
This produces O2 as a waste product!
What is RESPONSE??
-a reaction to a stimulus.
What is a stimulus?
-any change in the internal or
external environment of an
organism (temperature, weather,
light, predator).
e.g. blink, leaves fall off a tree,
leaves bend towards light
What is Homeostasis?
• Homeostasis is the body’s ability to maintain
a constant internal environment.
• Examples include:
– Maintenance of body temperature.
– Maintenance of pH.
– Maintenance of sugar level in the blood.
– Maintenance of water level in the body.
• Failure to maintain homeostasis will
result in the organism becoming sick or
dying!
What is GROWTH?
- building new parts for an organism
during metabolism.
- an increase in cell size.
- replace or repair of dying or dead
cells.
- maturation
r
e.g. a baby getting bigge , fruit
ripening
What is MOVEMENT?
- a change in position.
- a whole organism can move.
- internal organs, fluid, blood can
move.
- cell parts and cells can move.
What is REPRODUCTION?
- production of a new offspring or
organism.
2 types: 1) sexual – 2 parents
2) asexual – 1 parent
** NOT needed for the individual
organism to survive – just the
species.
Summary:
All forms of life share certain
characteristics. Living things are
able to move, perform complex
chemical activities, grow,
reproduce, and respond to stimuli.