Download contractile vacuoles

• Element-any substance that cannot be
broken down into simpler substances
– Ex: hydrogen and oxygen (periodic
table)
• Atom- smallest unit
of an element
• Compound- two or more elements
chemically combined
– Ex: Water H2O
• Molecule- smallest unit of most compounds
• Organic compound- a compound that
contains carbon
– The most important groups of organic
compounds found in living things are proteins,
carbohydrates, lipids, and nucleic acids.
• Inorganic compound- a compound that does
not contain carbon
– Ex: water or table salt
• Proteins-large organic
molecules made of carbon,
hydrogen, oxygen, nitrogen
and sulfur
– Foods high in protein: meat,
eggs, fish, nuts and beans
• Amino acids- small
molecules that make up
protein molecules
– 20 common amino acids
– Combine to form thousands
of proteins
• Enzymes- type of protein that speeds up a
chemical reaction in a living thing
– Ex: enzymes in saliva speed up digestion of food
• Carbohydrates- energy-rich organic
compound made of the elements carbon,
hydrogen and oxygen Ex: sugars and starches
• Lipids- fats, oils and waxes- energy-rich
organic compounds made of carbon,
hydrogen and oxygen
• Nucleic acid- very large organic molecules
made up of carbon, oxygen, hydrogen,
nitrogen and phosphorus
– Contain the instructions that cells need to carry
out all the functions of life
– Two kinds of nucleic acid
• DNA
• RNA
• DNADeoxyribonucleic
acid- genetic material
that carries info about
an organism that is
passed from parent to
offspring
• RNA- Ribonucleic
acid- plays an
important role in
production of proteins
• Selectively permeablesome substances can
pass through it while
others cannot
• Substances that can
move into and out of a
cell do so by one of
Picture of semipermeable
three methods:
– Diffusion
– Osmosis
– Active transport
membrane where red is blood,
blue is the dialysing fluid, and
yellow is the membrane.
Diffusion
• Process by which
molecules tend to
move from an area of
high concentration to
an area of low
concentration
– This is the main
method by which small
molecules move into
and out of a cell
Osmosis
• The diffusion of water
molecules through a
selectively permeable
membrane
– Water molecules move
from an area of high
concentration to low
concentration
If the concentration of solute (salt) is equal on both sides, the
water will move back in forth but it won't have any result on the
overall amount of water on either side.
"ISO" means the same
The word "HYPO" means less, in this case there are less solute
(salt) molecules outside the cell, since salt sucks, water will move
into the cell.
The cell will gain water and grow larger. In plant cells, the central
vacuoles will fill and the plant becomes stiff and rigid, the cell wall
keeps the plant from bursting
In animal cells, the cell may be in danger of bursting, organelles
called CONTRACTILE VACUOLES will pump water out of the cell
to prevent this.
The word "HYPER" means more, in this case there are more
solute (salt) molecules outside the cell, which causes the water to
be sucked in that direction.
In plant cells, the central vacuole loses water and the cells shrink,
causing wilting.
In animal cells, the cells also shrink.
Active Transport
• Movement of materials through a cell using
energy
• Passive Transport- movement of materials
through a cell with out using energy
• Transport proteinsthey “pick up”
molecules outside the
cell and carry them in
• Transport by
engulfing- first the cell
membrane surrounds a
particle, then it
pinches off and forms
a vacuole within the
cell