Topic 1 - Key Conecpts In Biology Flashcards
function of nucleus
stores genetic information and controls what happens in the cell
function of cytoplasm
where chemical reactions happen and it’s a jelly-like substance
function of a cell membrane
controls what goes in and out of the cell
function of the mitochondria
releases energy by aerobic respiration
function of ribosomes
where protein synthesis occurs (proteins are made)
function of chloroplasts
they contain chlorophyll (a green pigment) and chlorophyll absorbs light and photosynthesis occurs
function of vacuole
helps to support the plant and it stores cell sap
function of cell wall
it protects, supports and structures the plant and it contains cellulose
what organelles are only in plant cells and not in animal cells
chloroplast, vacuole and cell wall
a cell with a nucleus is describes as..
eukaryotic
a cell without a nucleus is described as…
prokaryotic
chromosomal DNA
giant loop of DNA containing most of the genetic material
plasmid DNA
small loops of DNA that carry extra information
flagella and its function
long whip like structures that allow the bacteria to move themselves along.
digestion
the breakdown of large insoluble molecules into smaller soluble molecules
biological catalyst
speed up chemical reactions in the body
what enzyme breaks down starch (a type of carbohydrate)
amylase
what enzyme breaks down protien
protease
what enzyme breaks down lipids
lipase
protien molecules break down into
individual amino acids
starch molecule breaks down into
glucose molecules
lipid molecule breaks down into
fatty acid chains and glycerol
resolution
ability to recognise the distance between two points as separate structures (level of detail)
magnification
the process of making something bigger
what is the test for starch
iodine solution
what colours do the iodine solution go if starch is/isn’t present
stays orange = no starch present
blue/black = starch present
what is the test for reducing sugars
benedict
what colours do the Benedict solution go if reducing sugar are/aren’t present
blue = no reducing sugar
orange/red = reducing sugar present
what is the test for protien
biuret solution
what colours do the biuret solution go if protein is/isn’t present
pale blue = no protien
purple = protien present
what is the test for lipids
ethanol emulsion
what colours do the ethanol emulsion go if lipids are/aren’t present
clear = no lipids
cloudy = lipids present
feild of view
circular area you see in a light microscope
how to work out total magnification
objective lens x eyepiece lens
how to work out the magnification using scale bar
image size / actual size
which is better an electron microscope or a light microscope
electron microscope - beams or electrons pass through a specimen to build up an image
specialised cell
a cell that has a specific function
what cell in the lining of the oviduct is adapted to help transport egg cells
hair like cilia which helps sweep her substance along
epithelial cells
cells that line structures in the body
what sub-cellular structures do prokaryotic cells not have
mitochondria or chloroplasts
what sub-cellular structure does bacteria not have and what does it have instead?
doesn’t have nuclei but has chromosomal DNA and plasmids instead
synthesis
building larger molecules from smaller subunits
polymer
large molecules made by bonding (chemically linking) a series of monomers
monomers
atoms or small molecules that bond together to form more complex structures such as polymers
enzymes
the biological catalyst that speeds up the breakdown and synthesis of molecules
substrates
the substance an enzyme works on
what enzyme synthesises DNA from its monomers
DNA polymerase
what do all enzyme names have in common
all end in -ase
food calorimetry
used to measure the heat transferred by burning a food sample
energy of food using calorimetry equation
energy in J/g =
mass of food (g)
active site
a region in an enzyme that binds to a substrate
lock and key model
a theory of enzyme action that explains how enzymes fit their substrate. The active site of an enzyme is structured to fit a specifically shaped substrate. Once the substrate binds to the active site, the enzyme will either break the molecule up into separate molecules OR bond the molecules to create one product molecule
denatured enzyme
when the shape of the active site has changed and the substrate no longer fits
optimum temperature
temperature at which enzyme works fastest
factors that effect the the rate of an enzyme controlled reaction are…
pH, temp, concentration of the substrate
diffusion
the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration
concentration gradient
a difference between two concentrations (higher concentration and lower concentration)
osmosis
a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one
semi-permeable
a membrane that allows some molecules through and not others
calculation for percentage change in mass
(final mass - initial mass) x100
initial mass
passive process and examples
diffusion and osmosis is a passive process which means it does not require energy
active transport
the movement of dissolved molecules into or out of a cell through the cell membrane, from a region of lower concentration to a region of higher concentration
passive transport - does it need energy?
no energy needed
active transport - does it need energy?
energy needed
magnification (size) equation
Image size of object / real size of object
what is the substance that strengthens the cell walls of a xylem cell
lignin
Where would you find the stem cells in plants?
Meristematic issue (meristem)
Name one place where you would find stem cells in animals.
Embryo
why do cells in the pancreas and small intestine have a lot of ribosomes
they need a high number of ribosomes because they are necessary to synthesise/produce the digestive enzymes being produced to digest the food
how do you measure the amount of energy in the food
calculate the change in temp (heat absorbed by the water)
how do eggs move into the uterus
the cilia lining the oviduct move side to side creating a current to move the egg
what does cilia lining the oviduct help to do
- help move the egg
- help secrete nutrients for support
why do potato cells not burst when placed in water
they have a cell wall which provides support
how can a student get a more accurate measurement of gas produced in an experiment
use a gas siringe
acrosome function
Contains digestive enzymes that breakdown the substances in the egg cells jelly coat -> allows sperm cell to borrow inside
Tail function (SPERM CELL)
Allows the sperm to swim to the egg
function of the cytoplasm being packed with nutrients (egg cells)
To supply the fertilised egg cell with energy for the growth of embryo
Changes in the cell membrane after fertilisation function (egg cell)
Jelly coat hardens to ensure only one sperm cell enters the egg
