Studied by 0 people
define cells
cells are the smallest units from which all organisms are made
what does unicellular mean? give 2 examples of unicellular organisms
unicellular means the organism is made of just a single cell. examples include bacteria and yeast
cellular differences between plant and animal cells [3]
1. plant cells have cell walls made of cellulose whereas animal cells don’t have cell walls
2. plant cells have chloroplasts containing chlorophyll whereas animal cells dont
3. plant cells have large vacuoles containing cellular sap whereas animal cells have much smaller vacuoles called vesicles
how are new cells produced?
by division of existing cells
cell membrane [3]
1. partially permeable so controls what goes in and out of the cell
2. made of proteins and lipids
3. separates the content of the cell from the rest of its surroundings
cell wall [3]
1. fully permeable
2. made of fibres through which bigger molecules can pass through
3. prevents cell from bursting when it absorbs too much water
cytoplasm [2]
1. clear, jelly-like substance
2. about 70% water, therefore metabolic reactions take place here
vacuole [3]
1. fluid filled space inside a cell surrounded by its own membrane
2. animal cell - small, called vesicles
3. plant cells - large and permanent, when full presses outwards on rest of cell which keeps it in shape
nucleus [2]
1. contains the DNA of the organism in the form of chromosomes
2. controls what the cell does
chloroplasts [2]
1. contain chlorophyll
2. contain starch grains (made during photosynthesis)
mitochondria
helps carry out aerobic respiration to release energy from glucose
ribosomes
help in protein synthesis
what are bacterica? [2]
unicellular organisms that don't have a nucleus
what are cells walls of bacterial cells made of?
peptidoglycan
differences between plant/animal cells and bacterial cells [3]
1. no nucleus
2. no chloroplasts
3. no mitochondria
what are plasmids
smaller circles of DNA
specialised cells have ______ _______
specific functions
ciliated cell found in and function
1. found in linings of trachea and bronchi in animals
2. moves mucus in trachea bronchi
neuron found in and function
1. found in the nervous system of animals
2. conducts electrical impulses
red blood cells found in and function
1. found in blood of mammals
2. transports oxygen
root hair cell found in and function
1. found in tips of roots of flowering plants
2. absorbs water and mineral ions
palisade mesophyll cell found in and function
1. found in the leaves of flowering plants
2. photosynthesis
sperm + egg cells found in and function
1. found in testes and ovaries of mammals
2. gametes used in reproduction
define tissue
a group of similar cells that work together to perform a particular function
define organ
a group of tissues that work together to perform a specific function
define organ system
several organs that work together to perform a specific function
magnification
magnification = image/actual
how many micrometres in an mm
1000
Note 
Flashcard (21)