topic 1 :key concepts in biology Flashcards
describe the cell structure of an animal cell
animal cell have a nucleus, cytoplasm, ribosomes, mitochondria and cell membrane
describe the cell structure of a plant cell
have the same organelles as an animal cell but they also contain chloroplasts, cell wall and a vacuole.
describe the cell structure of a bacterial cell.
bacteria cells contain some similaritiess with the plant and animal cells ( cell membrane and cytoplasm) however they have unique organelles such as: chromosmal dna, plasmid dna, flagella and cell wall.
what is the difference between prokaryotic and eukaryotic?
what are specialised animal cells?
specialised animal cells are cells that have undergone
what are light microscopes used for?
used to study living cells and get a rough idea of the structure of the cells.
what are elctron microscopes used for?
electon microscopes use a beam of electrons instead of light to get an image of up to 1,000,000 x its regular size. able yo clearly see all organelles and structures of all kinds of cells.
how do you calculate magnification of microscope
magnification of eypiece lens * objective lens magnification
what is resolution
the closest distance that can be distinguished between 2 points.
what is the equation to calculate magnification?
magnification =size of image/real size of object
what are enzymes
proteins that function as a biological catalyst
what happens when an enzyme denatures?
the active sight of the enzyme is changed resulting to the enzyme being unable to react and break down the substrate
how does temperature and ph affect an enzyme
temperature and ph affects wether the enzymes active site is able to remain the same shape, deciding the rate of reaction of wether the enzyme denatures
how does enzyme concentration effect enzyme reaction rate
As the substrate concentration increases so does the rate of enzyme activity. An optimum rate is reached at the enzyme’s optimum substrate concentration
what are carbohydrates, what enzyme breaks them down and where are they found?
carbohydrates are large molecules made from monosaccharides ( simple sugars). they are broken down by carbohydrase that are found in saliva, the pancreas and small intestine.
what are proteins, what enzyme breaks them down and where are those enzymes found?
proteins are large molecules made from amino acids. protease is the enzyme that breaks down proteins. it is found in the stomach, pancreas and small intestine.
what are lipids, what breaks them down and where are these enzymes found ?
lipids are large molecules made from smaller units of fatty acids and glycerol.
digestive enzymes lipase break them down which are produced in the pancreas and small intestine
what is diffusion?
Diffusion is the passive transport in cells, where substances move from an area of high concentration to an area of low concentration.
what is osmosis?
Osmosis is the diffusion of water molecules, from a region of higher concentration to a region of lower concentration, through a selectively permeable membrane.
what is active transport?
Active transport is the movement of substances against a concentration gradient using energy. (low to high concentration)
