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
Coenzyme
non-protein organic molecules that are essential for the functioning of an enzyme
Cofactor
the ions or inorganic molecules required by enzymes to catalyse a reaction
Denature
to change the molecular structure of a protein by heating, a change in pH, adding detergents or shaking
Enzyme
an organic substance that increases the speed of chemical changes without being altered or destroyed in the change; an organic catalyst
Enzyme inhibitor
a substance that slows or stops an enzyme’s activity
Enzyme-substrate complex
the structure formed when an enzyme and a substrate combine
Substrate
a molecule upon which an enzyme acts
Pleura
a membrane covering the surface of the lungs
Pleural fluid
a thin layer of fluid within the pleura that allows the lungs to move during breathing
ventilation
The process of inhalation and exhalation
aggulination
The clumping together of micro-organisms or of blood cells
antibody
A substance produced in response to a specific antigen; it combines with the antigen to neutralise
antigen
Any substance capable of causing the formation of antibodies when introduced into the tissue
autologous transfusion
A transfusion using the patient’s own blood
coagulation
Formation of a blood clot
cryoprecipitate
A blood product used in transfusions; produced by freezing the plasma and thawing it slowly
haematocrit
The ratio of red blood cells to the total volume of blood
haemophilia
An inherited disorder in which the blood clots slowly or not at all
Lymphoid tissue
tissue containing many lymphocytes and macrophages
Pericardium
membrane enclosing the heart
Phagocytic cell
cell that can engulf and digest micro-organisms and cell debris
Semilunar valve
valve preventing blood from flowing back into the ventricles; located at the start of the aorta and pulmonary artery
Vasoconstriction
Decrease in the diameter of blood vessels, restricting the flow of blood
Vasodilation
Increase in the diameter of blood vessels, increasing the flow of blood
bile
Secretion of the liver, stored in the gall bladder and released into the small intestine
bile salts
Substances that break fats into tiny droplets
chemical digestion
The breakdown of food to small molecules by chemicals
Coelic disease
an autoimmune disease due to the immune system reacting to gluten
Elimination
removal of indigestible material, bacteria and bile pigments from the body
Emulsify
to mix two liquids that would not normally mix
Gastric gland
the secretory unit of the stomach located in the gastric pits; produces gastric juice
Gastric juice
the digestive juice secreted by the glands of the stomach
Intestinal juice
the digestive juice secreted by the glands of the small intestine
Lacteal
A lymph capillary in the small intestine; absorbs fat from digested foods
mastication
The process of chewing; to grind or crush food with teeth
mechanical digestion
The mechanical breakdown of food into small particles
peristalsis
Waves of muscular contraction that push food along the alimentary canal
pyloric sphincter
A ring of smooth muscle between the stomach and the duodenum
ribonuclease
An enzyme in pancreatic juice that digests RNA
Salivary gland
gland in the mouth that secretes saliva
Segmentation
a process occurring in the small intestine which uses the contraction of circular muscles to push the chyme into segments, mixing it with digestive juices
Trypsin
an enzyme in pancreatic juice that breaks down protein; also known as pancreatic amylase
Deamination
the removal of the amino group from an amino acid molecule
Dialysis
a method of removing waste from the blood when kidney failure occurs
Excretion
removal of the wastes of metabolism from the body
Facultative reabsorption
the process whereby carrier proteins assist the movement of substances through the cell membrane
Glomerular filtration
the filtration of blood in the kidney
Haemodialysis
process in which blood is passed through an artificial kidney or dialysis machine
Nephron
functional unit of the kidney
Peritoneal dialysis
dialysis occurring inside the body, using the peritoneum as the membrane across which wastes can be removed
Peritoneum
the membrane that lines the inside of the abdominal cavity
Selective reabsorption
the reabsorption of some substances and not others in the renal tubules
Tubular secretion
the process whereby ions and drugs are secreted from the blood into the kidney tubule
Contractibility
ability to contract
extensibility
The ability of muscle fibres to be stretched when pulled
Elasticity
the abilitity of muscle fibres to return to their original length after being stretched
