sem 1 yr.11 exam Flashcards
Accuracy
extent to which the measurements are correct
Blind experiment
an experiment where the subjects do not know whether they are receiving the test treatment or the placebo
Double blind experiment
an experiment where neither the subject nor the experimenter knows who receives the test treatment or placebo
Fair test
test that only changes the independent variable and controls all other variables to test hypothesis
Placebo
a substance or procedure that has no active substance but is used as a control test
Reliability
the extent to which an experiment gives the same result each time it is performed
Validity
the extent to which an experiment tests what it is supposed to test
Active transport
The use of energy to move substances, usually ions, across a cell membrane against the concentration gradient
carrier-mediated transport
Transport of ions or molecules across a cell membrane by special carrier proteins
cellular respiration
The chemical reactions that make energy available for the cell
carrier protein
A protein that carries substances from one side of the cell membrane to the other
channel protein
A protein that allows ions, water and small molecules to pass through the cell membrane
concentration gradient
A difference in concentration of a solution, often between the inside and outside of a cell
connective tissue
Tissue providing support for body organs
diffusion
The movement of particles of a liquid or a gas so that they are distributed evenly over the available space
endocytosis
The process by which a cell takes in materials by enfolding and enclosing them
epithelium
Tissue that forms the outer part of the skin and that lines hollow organs and ducts
exocytosis
The process whereby the contents of the vesicles of cells are pushed out through the cell membrane
facilitated diffusion
The process whereby proteins allow the movement of substances through the cell membrane along the concentration gradient
facilitated transport
Proteins in the cell membrane allow molecules to be transported across the membrane
homeostasis
The maintenance of a relatively constant internal environment despite fluctuations in the external environment
inclusion
Chemical substances inside a cell in the form of granules or droplets
matrix
Non-cellular material between the cells of a tissue
osmosis
The diffusion of water molecules through a differentially permeable membrane from an area of higher water concentration to an area of lower water concentration
osmotic pressure
The pressure due to differences in concentration on either side of a differentially permeable membrane
Phagocytosis
the process by which a cell surrounds, and takes in, solid particles
Pinocytosis
the process by which cells enfold, and takes in, drops of liquid
Protein channel
a pathway though a protein in the cell membrane that allows the passage of substances across the membrane
Simple diffusion
the process of substances moving along the concentration gradient in a solution or across a semipermeable membrane, without the use of membrane proteins
Solvent
a substance, often water, in which a solute is dissolved
Vesicle
a small membrane-bound cavity in the cytoplasm of a cell, smaller then vacuoles
Vesicular transport
the transport of materials into or out of a cell in membrane-bound sacs; also called bulk transport
Activation energy
the energy needed to break the bonds of the reacting particles in a chemical reaction; the energy needed to start a chemical reaction
Aerobic respiration
respiration requiring oxygen
Anabolism
the process of combining small molecules to make larger ones; it requires energy
Catabolism
chemical reactions that break down large organic molecules into smaller ones, with the release of energy
catalyst
A substance that lowers the activation energy of a reaction, increasing the rate of the reaction without being consumed