CELLS GLOSSARY Flashcards
Active site
A specific shaped part of an enzyme where the substrate fits.
Active Transport
The movement of molecules from an area of low conc. to an area of high conc. which requires energy.
Aerobic respiration
Respiration in the presence of oxygen.
Anabolic enzyme
An enzyme that takes small molecules and joins them together.
Catabolic enzyme
An enzyme which takes large molecules and breaks them up.
Cell wall
Rigid layer of cells found only in plants.
Chlorophyll
Pigment found in plants which gives the plant its green colour.
Chloroplast
Site of photosynthesis.
Cristae
The folds of the mitochondria where the electron transfer chain occurs.
Denature
The changing in the shape of the active site of an enzyme so the substrate can no longer fit - caused by high temp and incorrect pH. Weak hydrogen bonds breaking easily.
(Deprived of its natural properties)
Deoxyribose Nucleic Acid
DNA
Diffusion
The movement of particles from an area of high concentration to an area of low concentration.
DNA replication
The copying of DNA before the cell divides.
Enzymes
Proteins that are biochemical catalysts which speed up biochemical reactions in an organism.
Facilitated diffusion
A form of passive transport where molecules move across the cell membrane through the membrane proteins (channels).
Flaccid
A cell that is limp and floppy.
G1 of cell cycle
The stage in the cell cycle where the cell grows and does its job.
G2 of cell cycle
The stage in the cell cycle where the replicated chromosomes are checked for mistakes.
Golgi body
Proteins are modified and packaged
Grana
Stacks of thylakoids within the chloroplast, where the light dependent stage occurs
Hypertonic solution
A solution with a high conc. of solute, therefore a low conc. of water
Hypotonic solution
A solution with a low concentration of solute, therefore a high concentration of water
Induced fit model
The enzyme model where the enzyme changes its shape after bonding with the substrate
Inhibitors
Poisons that bind to the active site of enzymes, preventing them from catalysing reactions
Isotonic solution
A solution which has the same osmolarity or solute concentration as another solution
Lock and key model
The model that explains how enzymes work and where the enzyme is a rigid structure
Matrix
Fluid-filled space of enzymes in the mitochondria where the krebs cycle occurs
Mitochondria
Organelle in cell where respiration occurs
Mitosis
The stage of the cell cycle where the replicated chromosome is split into two cells
Osmosis
The movement of water from an area of high concentration to an area of low concentration through a semi-permeable membrane
Palisade layer
Part of the leaf where most chloroplasts are found, so most photosynthesis occurs here
Passive transport
The movement of molecules from an area of high concentration to an area of low concentration which doesn’t require energy
Phagocytosis
A form of active transport by which a cell uses its plasma membrane to engulf a large solid particle
Pinocytosis
A form of active transport where fluids and nutrients are ingested by cells
Ribosomes
Part of cell where protein synthesis occurs
S stage of cell cycle
The stage in the cell where the DNA is replicated
Semi-conservative replication
Where one half of the new DNA molecule is an intact strand from the parent DNA
Semi permeable membrane
A membrane that allows some substances to pass through it but not others
Stroma
Part of the chloroplast where the light-idependent stage occurs
Turgid
A cell that is swollen, bloated, puffed up or inflated
Proteins
Large, complex molecules made up of amino acids, and carry out functions in the body
Polypeptide chain
A chain of specific amino acids, folded into a specific shape, to form a particular protein
Independent variable
The variable we change, always goes on the x-axis (horizontal)
Dependent variable
The variable we measure/count, always goes on the y-axis (vertical)
Temperature affecting rate of reaction
The higher the temperature, the more kinetic energy particles have. Particles that move quicker with more energy increase the chance of successful collisions.
Concentration affecting rate of reaction
Increasing the concentration of reactants means there are more particles present for more sufficient and successful collision:
Surface area affecting rate of reaction
Increasing the surface area of a reactant means there are more particles exposed for collisions with the other reactant particles. This increases the chance of more sufficient and successful collisions
Catalysts
Speed up the rate of reaction, but are not used up in the reaction.
