Download Six characteristics of all living things

Characteristics and Needs of Living Things
Six characteristics of all
living things (organisms)
Four basic needs of all
living things
Need for energy
Need for water
1. Cellular organization
All organisms made of cells – basic unit of structure and
function in an organism
Unicellular – single celled
Multicellular – multi celled
2. Cellular composition
Water - Most abundant chemical in cells. It is
needed for metabolism.
carbohydrates (energy source)
proteins and lipids (building materials)
nucleic acids (genetic material that directs cell’s
activities).
3. Energy use
Cells use energy to perform work
All living things require energy
Primary source of energy is the sun
Food + Oxygen = ATP (energy)
4. Growth and development
Growth – becoming larger
Development – change that occurs during cell’s life to
become more complex
5. Response to surroundings
Cells react to changes in their surroundings called a
stimulus. Ex: light, temp, sound. This action or change in
behavior is called a response.
6. Reproduce
Cells produce offspring that are similar to the parents
1. energy 2. water 3. living space (competition)
4. stable internal conditions (homeostasis)
Cells must have food as their energy source.
Autotrophs-organisms that make their own food (selffeeder) ex: plants
Heterotrophs-organisms that cannot make their own food
(other-feeder) ex: animals, mushrooms, slime molds
Most organisms can only live a few days without water.
Organisms need water to:
 Obtain chemicals from their surroundings
 Break down food
 Grow
 Move substances within their bodies
 Reproduce
(Water can dissolve more chemicals than
any other substance on earth.)
Need for living space
Need for stable internal
conditions
All organisms need place to live, get food and water, find
shelter. Limited space causes competition. Plants
compete for space for leaves, roots. Animals move and
compete for space
Organisms must be able to keep conditions inside body
constant even when surroundings change. Homeostasis –
maintenance of stable internal conditions despite changes
in the surroundings.
Discovering Cells and Microscopes
Invention of microscope
Robert Hooke
Anton van Leeuwenhoek
Matthias Schleiden
Theodor Schwann
Rudolf Virchow
Cell theory
Microscope
Electron microscope
Made it possible to discover and learn about cells.
Uses lenses and light to magnify objects. Compound
microscope has more than one lens
Using thin slices of cork was one of first people to
observe cells. Looked like tiny rooms so he called
them cells.
Looked at pond water and saw one-celled organisms
which he called animalcules (little animals). Looked at
teeth scrapings and was first person to observe
bacteria.
Concluded that plants were made of cells.
Concluded that all animals are made of cells.
Proposed that new cells were formed from existing
cells
all living things are composed of cells
cells are the basic unit of structure and function
in living things
all cells are produced from other cells
Magnification – ability to make things look larger by
use of lenses and light.
Resolution – ability to clearly distinguish individual
parts of an object
Uses beam of electrons instead of light to examine a
specimen. Much higher resolution.
Cell Structures
Organelles
Cell wall
Cell membrane
Nucleus
Cytoplasm
Organelles in the nucleus
Organelles in the cytoplasm
Small structures within cells - carry out specific
functions
Rigid outer layer made of cellulose - surrounds plant
cells. Helps protect and support.
Found in both plant and animal cells. Controls what
moves in and out of cell. Maintains homeostasis.
Large, oval structure. Brain or control center of the
cell directing all activities.
Clear thick jelly-like fluid between the cell membrane
and the nucleus.
Nuclear membrane - Surrounds the nucleus and
protects it.
Chromatin - Thin strands floating in nucleus. Contain
genetic material and direct functions of the cell.
Nucleolus - Small object in nucleus which is where
ribosomes are made. Ribosomes produce proteins.
Mitochondria – rod shaped structures. Powerhouse
of the cell - produce most of the energy.
Endoplasmic reticulum – passageways which carry
proteins and other materials.
Ribosomes – grainlike bodies attached to
endoplasmic reticulum. Produce proteins and pass
them to the er.
Golgi bodies – flattened sacs that receive proteins
and other materials from ER, package them, and
distribute them to other parts of the cell. Also release
materials outside the cell.
Chloroplasts – Large green structures in plant cells.
Capture energy from sunlight and use it to produce
food. Give plants their green color
Vacuoles – round, water-filled storage sac. Store
food, materials and waste products. When full of
water make the plant firm. Plants have one large –
animals usually do not have.
Lysosomes – small structures that contain chemicals
that break down large food particles into smaller
ones. Also break down old cell parts – cleanup crew.
Bacterial cells
Specialized cells
Levels of organization
Differences between plant,
animal and bacterial cells
Different from plant and animal cells - eukaryotes
usually smaller
does not have a nucleus – prokaryotes
genetic material found in cytoplasm
only contain ribosomes – none of the other
organelles
Vary greatly in size and structure. Each carries out a
different specific function. Structures are suited to
function.
cells  tissues organs organ systems 
organism
1. Plant cells have cell walls, chloroplasts, and one
large vacuole.
2. Plant cells have a somewhat rectangular shape.
3. Animal cells do not have cell walls or chloroplasts
4. Animal cells have several small vacuoles.
5. Animal cells have a somewhat spherical shape.
6. Bacterial cells have no nucleus– the genetic
material is in the cytoplasm.
7. Bacterial cells have a cell wall and a cell
membrane.
8. Bacterial cells are much smaller than plant and
animal cells. They lack most of the organelles found
in plant and animal cells.