cells part 1
diffusion
prokaryots and eukaryots
8 things all organisms do
grow
respiration
sensative
reproduce
extretion
movement
nutrition
control internal conditions (homeostasis)
move from place to place
make more of the same species
respond to surroundings
getting bigger
release of energy from food by reaction with oxygen
removing waste
digesting and absorbing nutrients to create energy through respiration
control body temperature
prokaryots
eukaryots
examples
examples
prokaryots are small, do not have a nucleus, they do not have organelle
Eukaryots are bigger, have a nucleus and organelle
plant cells
bacteria
fungi
animal cells
protoctist
virus and pathogens
mitochondria-turn glucose and oxygen to energy
cell membrane-holds the cell together and controls what comes in and out
cytoplasm-where the chemical reactions happens
nucleus- controls what the cell does
ribosome- a small organelle where proteins are made in the cell
cell wall-made of cellulose gives support for the cell
vacuole-contains cell sap, a weak solution of sugar and salts
green chloroplasts- containing chlorophyll for photosynthesis
They are single caled organisms. Some like amoeba live in ponds of water. They have chlorella, chloroplast and are more like plants. Most of them are harmless but some may harm as Plasmodium causing malaria. They have a flangellum( tail) to swim
They are single organisms. They are very small. They have a cell wall, cell membrane, cytoplasm and plasmoid ( small rings of DNA) They don't have nucleus. They carry out Photosynthesis
osmosis
Active transport
semi permeable membrane
diffusion
The movement of molecules from an area of high concentration to an area of low concentration
The movement of water molecules from a high concentration to low concentration
The movement os a substance from low concentration to high concentration
This process requires energy
Allows some molecules to pass but not large molecules
osmosis ad semi-permeable membranes
A microorganism that causes a disease on another organism
hypertonic solution
hypotonic solution
isotonic solution
An isotonic solution is one that has the same concentration as inside the cell. There are the same number of free water molecules on both sides the membrane
A hypertonic solution has a higher solute concentration than inside the cell.There are fewer free water particles inside the cell than outside
A hypo tonic solution is one that has a lower solute concentration than inside the cell. There are more free water molecules inside the cell than outside
bursts
shrinks
.
animal cell
plant cell
hypotonic
hypertonic
The cell becomes Plasmolyzed
The cell becomes turgid
The water flows inside the vacuole.The vacuole expands pulling the cytoplasm away from the cell wall.
Water flows outside the vacuole. The vacuole shrinks pushing the cytoplasm out against the cell wall
diffusion ca be affected by different things like
temperature
distance
the concentration gradient
size of the molecule
surface area to volume
solutions
solvent
concentration
solute
the amount of sloute dissolved in a solution (a solution can be dilute or concentrated
The liquid which dissolves the solute
A substance dissolved un a solution
isotonic
the cell becomes flaccid
provide structural suport
more water, less sugar
less water, more sugar
cell swells
cell shrivels
Plants, some bacteria and algae get food through photosynthesis
Animals, funguses and bacteria et food by eating other organisms
Examples might be removal of CO2 or urea
plants move to try to face the sun
Features
normally have nervous coordination
able to move from place to place
often store carbohydrates as glycogen
feed on organic substances
Multicellular organisms
features
feed through photosynthesis
store carbohydrates as starch
Multicelular structures
don't have nervous coordination
Contain a nucleus
features
cell walls made of chitin
Don't have chloroplast to carry out photosynthesis
normally multicellular but can be unicellular
Feed by releasing enzymes onto the food and then absorbing and digesting the food
Don't have nervous coordination
features
An example of a virus in plants is tobacco mosaic virus, which decolour the leafs
Multicellular fungi are mainly made up of thread-like structures known as hyphae that contain many nuclei and are organised into a network known as a mycelium
divers group of organism that don't belong iany other group
Mainly single celled organisms
In this group the structure of the cell varies and they can be more like animal or plant cells
Some protoctist make food through digestion and others feed on organic substances
No nervous cordination
Features
single celled organisms
No nucleus but contain circular DNA
Some bacteria produce food through photosynthesis
Some bacteria feed from dead organisms
pathogens can be
fungi
protoctists
bacteria
VIruses
Pathogenic bacteria do not always infect the hosts of cells, they can remain within body cavities or spaces
an example of a bacterial desease is tuberculosis
common in plants and animals and are much more severe as they can affect the entire organism
An example of a fungal disease would be black sigatoka or cordiceps
Plasmodium falciparum is a protoctist that causes severe forms of malaria in humans
Levels of organisation
Cells are the basic building blocks in an organism
an organism can be
Unicellular
Multicellular
Only contain 1 cell
Contain multiple cells
Cells are made up of of structures called organelles, for example the nucleus, mitochondria or ribosomes
In multicellular organisms cells are specialised for a specific function
A group of specialised cells form tissues
The tissues form organs
The organs form an organ system
Levels in an organism
Tissues
Organs
Cells
Organ systems
Organelles
A component withina cell that carries out a specific task
Basic functional and structural units in a living organism
A group of cells of similar structure working together to perform a particular function
Made of a group of different tissues working together to perform a particular function
Made of a group of organs with related functions, working together to perform body functions within the organism
Movement of substances
Diffusion
The movement of molecules from a region of higher concentration to a region of lower concentration
Diffusion in living organisms
Molecules move into or out of living cells by diffusion when they cross the cell membrane
This happens because the cell membrane is semi permeable which means they allow some molecules to pass, but not others
difussion in living organisms
gaining nutrients from the digestive system
Gain oxygen in the lungs
remove waste from lungs and kidneys
Osmosis
The movement of water molecules from a region of higher water concentration (a dilute solution) to a region of lower water concentration (a concentrated solution), through a partially permeable membrane
semipermeable membrane allows movement of water through it but it does not let sugar go through as it is a big molecule
Osmosis in plant cells
Due to cell walls, plant cells are protected from bursting
Active transport
The movement of particles across a cell membrane from a region of lower concentration to a region of higher concentration
Energy is needed for active transport
examples of active transport in the human body
Absorbtion of products of digestion into the bloodstream
absorption of mineral ions from the soil into the root hair cells of plants
Factors affecting the rate of movement of substances
Temperature
Diffusion distance
Concentration gradient
Surface area to volume ration
The bigger a cell or structure is, the smaller its surface area to volume ratio is, slowing down the rate at which substances can move across its surface
Cells adapted for diffusion have an increased surface area
The shorter the distance the molecule needs to travel the faster the process will be
The higher the temperature, the faster molecules move as they have more energy
The greater the difference in concentration on either side of the membrane, the faster movement across it will occur
Practical:investigation of diffusion and osmosis
Parts of a bacteria
plasimoid
Contains the DNA of the bacteria
ribosomes
Cellular machine used to make proteins
Cell walls made of cellulose
Cell wall made out of chitin
Contains mcillium
click to edit