AQA Biol1 Glossary

?
  • Created by: lucie
  • Created on: 16-05-13 18:53
Absorption
The passing of digested food molecules through the gut wall and into the blood
1 of 120
Activation Energy
The minimum amount of kinetic energy needed for a reaction to occur
2 of 120
Active Site
The place on an enzyme where a substrate molecule is temporarily bound during a chemical reaction. It is complementary in shape to the substrate.
3 of 120
Active Transport
The movement of molecules across a membrane from an area where they are in lower concentration to an area where they are in higher concentration, using specialised transport molecules, and using ATP energy.
4 of 120
Aerobic Respiration
Respiration using oxygen.
5 of 120
Alpha Helix Structure
A form of secondary structure in a protein. It consists of a long polypeptie chain held in a helix by hydrogen bonds.
6 of 120
Alveolus
A tiny air sac in the lungs where gas exchange occurs
7 of 120
Amino Acid
The monomer used as the building block of polypeptides and proteins. Each has an amino -NH2 and a carboxylic acid group - COOH
8 of 120
Amylase
An enzyme that digests starch into maltose
9 of 120
Anaerobic Respiration
Respiration without using oxygen
10 of 120
Antibody
A protein produced by plasma cells that binds specifically to an antigen
11 of 120
Antigen
A large molecule, usually on the surface of a cell, that triggers an immune response
12 of 120
Aorta
A major artery that takes oxygenated blood from the left ventricle of the heart round the body
13 of 120
Artery
A blood vessel that carries blood away from the heart
14 of 120
Asthma
An allergic response in which the airways become narrowed, causing difficulty in breathing
15 of 120
Atheroma
Fatty deposits that build up in the wall of an artery. This is the underlying cause of coronary heart disease.
16 of 120
ATP
The immediate source of energy in biological reactions. ATP loses a phosphate group to become ADP, releasing energy.
17 of 120
Atrioventricular node
A mass of specialised heart tissue that delays the wave of electrical excitation from the sinoatrial node for a fraction of a second. This allows the atria to empty completely before the ventricles contract.
18 of 120
Atrioventricular Valve
A valve in the heart between the atrium and ventricle, which closes to stop blood flowing backwards into the atrium from the ventricle.
19 of 120
Atrium
An upper chamber of the human heart. It has relatively thin walls.
20 of 120
B-Cells
These cells form part of the immune system and produce plasma cells that make antibodies, as well as memory cells.
21 of 120
Benedict's Solution
A blue solution used to test for the presence of reducing sugars, such as glucose and maltose.
22 of 120
Beta - Pleated Sheet
A form of secondary structure in a protein in which part of the polypeptide chain forms flattened, pleated areas held together by hydrogen bonds.
23 of 120
Bilayer
A double layer of phospholipid molecules that make up the main part of the cell surface membrane.
24 of 120
Binding
Forming a temporary bond between a substrate and the active site of an enzyme, or between a membrane protein and the substance it recognises.
25 of 120
Biuret Solution
A solution used to test for the presence of proteins. The blue solution is added to a sample, and if a protein is present, it turns lilac.
26 of 120
Bronchi
There are two branches from the trachea that carry air towards (or away from) the lungs.
27 of 120
Bronchioles
Small tubes branching from the bronchi in the lungs
28 of 120
Buffer
A solution that maintains a pH. It is often used in enzyme investigations to ensure that pH remains constant.
29 of 120
Capillary
A microscopic blood vessel that carries oxygen to the tissues
30 of 120
Capsule
A slimy layer found on the outside of some bacterial cells.
31 of 120
Carbohydrates
A class of compounds made of carbon, hydrogen and oxygen. This group includes sugar such as glucose and sucrose, as well as polysaccarides such as starch and cellulose
32 of 120
Cardiac Cycle
The sequence of events that make up the heartbeat
33 of 120
Carrier Protein
A protein that carries molecules of a specific type across a cell membrane.
34 of 120
Cell
The building block of which all living organisms are composed
35 of 120
Centrifuge
A device that spins at high speed, separating the denser components out of a suspension to form a solid pellet, while the less dense components remain suspended in the liquid supernatant.
36 of 120
Channel Protein
A protein or pore that spans the cell surface membrane and allows molecules of a specific type to pass through by facilitated diffusion
37 of 120
Cholera
Disease caused by a bacterium that releases a toxin called CT. This toxin activates a protein in the gut that transports chloride ions into the gut. This lowers the water potential in the gut and causes diarrhoea
38 of 120
Competitive Inhibitor
A molecule that is similar in shape to a substrate molecule that can bind to an enzyme's active site, preventing the substrate molecule from binding.
39 of 120
Complementary
Two substances that have shapes that allow them to fit together.
40 of 120
Concentration Gradient
A difference in the concentration of a substance between two areas
41 of 120
Condensation Reaction
A reaction that forms a bond and removes a molecule of water.
42 of 120
Coronary Artery
These are arteries that supply oxygenated blood to the heart muscle
43 of 120
Correlation
This is when a change in one variable is reflected by a change in a second variable
44 of 120
Co-transport
This is when one molecule is taken into a cell using a protein in the cell membrane, alongside another molecule or ion. For example, glucose enters the epithelium of the gut alongside a sodium ion.
45 of 120
Cristae
The folds in the inner membrane of the mitochondrion that increase the surface area for ATP production
46 of 120
Cytoplasm
The watery solution in a cell that is outside the membrane-bound organelles
47 of 120
Denaturation
This happens to an enzyme when its tertiary structure is changed, so its active site is no longer the right shape for the substrate to fit in.
48 of 120
Diaphragm
A sheet of muscle that separates the thorax from the abdomen. It contracts when a person breathes in.
49 of 120
Diastole
The period in the cardiac cycle when the atria and ventricles are relaxing.
50 of 120
Diffusion
The movement of molecules or ions from a region where they are in higher concentration to a region where they are in lower concentration down a concentration gradient.
51 of 120
Digestion
Breaking down large molecules into smaller, soluble molecules that can be absorbed.
52 of 120
Disaccaride
A sugar made when two monosaccarides join together, e.g. sucrose and maltose.
53 of 120
Disulfide Bridge
This is a strong covalent bond formed between the R-groups of some amino acids. These bonds hold protein in their tertiary structure.
54 of 120
Duodenum
The first part of the digestive system.
55 of 120
Electron Microscope
A microscope that uses electron beams and magnetic lenses to produce a magnified image of an object.
56 of 120
Emphysema
A disease in which the walls of the alveoli break down, reducing the surface area for gas exchange. The patient becomes breathless.
57 of 120
Emulsion Test
This a test for lipids. You shake the substance up with ethanol, then add an equal volume of water. If a lipid is present, it goes milky.
58 of 120
Endoplasmic Reticulum
System of phospholipid membranes extending through most of the cell, divides the cell up into compartments. There are two types: Smooth ER and Rough ER.
59 of 120
Enodthelium
Layer of cells lining an internal tissue, eg the lining of an artery or the wall of a capillary
60 of 120
Enzyme
A protein with a complex tertiary structure that lowers the activation energy for a reaction to occur. It has an active site that is specific for a particular substrate.
61 of 120
Epithelium
The tissue that covers the surfaces of the body and its organ, e.g. the alveoli.
62 of 120
Eukaryotic Cell
A cell containing membrane-bound nucleus and membrane-bound organelles such as mitochondria and endoplasmic reticulum.
63 of 120
Expiration
Breathing out
64 of 120
Facilitated Diffusion
Diffusion across a membrane involving protein channels or carrier molecules.
65 of 120
Fatty Acid
An organic molecule consisting of a hydrocarbon tail and a carboxylic acid group. R-COOH
66 of 120
Fibrosis
A lung disease caused by breathing in dust and dirt. It causes the walls of the alveoli to become thicker, making gas exchange less efficient.
67 of 120
Flagellum
A long 'whip-like' structure used for movement in some organisms, e.g. bacteria.
68 of 120
Fluid Mosaic Model
A model of the cell surface membrane, which has mobile proteins scattered among phospholipids which move around gently.
69 of 120
Fructose
A monosaccaride that is found in the disaccaride sucrose.
70 of 120
Galactose
A monosaccaride that joins with glucose to make lactose
71 of 120
Glucose
A monosaccaride with the formula C6H12O6
72 of 120
Glycerol
An organic compound which combines with fatty acids to form a lipid.
73 of 120
Glycoprotein
A protein with a carbohydrate attached.
74 of 120
Golgi Body/Apparatus
Stack of flattened membrane-bound sacs in which proteins are processed and packaged for export out of the cell in secretory vesicles.
75 of 120
Homogeniser
Equipment used to break open and homogenise cells during cell fractionation
76 of 120
Hydrogen Bonds
A weak bond that forms between R-groups of different amino acids in the polypeptide chain. These bonds hold proteins in their secondary and tertiary structures.
77 of 120
Hydrolysis
The breaking down of large molecules into smaller soluble ones by breaking bonds with the addition of water.
78 of 120
Hydrophillic
This term is used to describe the 'head' of a phospholipid which arranged itself towards water.
79 of 120
Hydrophobic
This term is used to describe the 'tail' of a phospholipid which arranges itself away from water.
80 of 120
Ileum
Part of the small intestine where dissolved nutrients are absorbed.
81 of 120
Immune System
The way that the body that the body responds to infection by a pathogen, using B-cells and T-cells.
82 of 120
Induced Fit
This theory explains how enzymes work. The active site changes shape as the substrate binds to make a close fit. The reaction occurs and the products are released.
83 of 120
Inspiration
Breathing in
84 of 120
Intercostal Muscles
The muscles between the ribs that contract and relax to raise and lower the rib cage during breathing.
85 of 120
Iodine Test
This is a test for starch - you add this solution, and if starch is present it goes blue-black
86 of 120
Isotonic
A solution that has the same water potential as the cell, so does not allow net movement of water into or out of the cell.
87 of 120
Lactose
A disaccaride made when glucose and galactose join together, found in milk.
88 of 120
Lactose Intolerance
A person who does not have enough lactase enzyme to digest the lactose normally present in the diet.
89 of 120
Lipase
An enzyme that hydrolyses lipids
90 of 120
Lipid
A molecule made up of fatty acids attached to a glycerol molecule.
91 of 120
Lock and Key
This theory explains how enzymes work. The substrate fits exactly into the enzyme's active site, reducing activation energy causing a reaction to occur.
92 of 120
Lumen
The hollow cavity inside a tubular structure such as the gut or a blood vessel.
93 of 120
Maltose
A disaccaride made when two glucose molecules join together.
94 of 120
Microvilli
Tiny finger-like projections from the cell surface membrane of some animal cells, e.g. those lining the small intestine. They increase the surface area for absorption.
95 of 120
Mitochondria
The organelle that carries out aerobic respiration and produces most of a cell's ATP.
96 of 120
Monoclonal Antibodies
Name given to antibodies that are all same, and specific to one antigen. They are used, for example, in pregnancy test kits or in targeting drugs to cancer cells.
97 of 120
Monomer
One of many similar smaller molecules that join together to form a polymer.
98 of 120
Monosaccaride
A single sugar, such as glucose or fructose.
99 of 120
Myobacterium Tuberculosis
The name of the bacterium that causes TB.
100 of 120
Myocardial Infarction
The name for a heart attack. This happens when the coronary artery is blocked by a blood clot or atheroma, so the heart muscle is starved of oxygen and some of the heart muscle cells die.
101 of 120
Myogenic
This describes the cardiac muscle, which can contract on its own without any impulses from the nervous system.
102 of 120
Non-Competitive Inhibitor
This fits into an enzyme, but not at its active site. However, it changes the shape of the active site so that substrate no longer fits.
103 of 120
Non-Reducing System
A sugar that gives a negative result with Benedict's test but a positive result with Benedict's test after it has been hydrolysed by boiling with acid and neutralised by adding an alkali, eg sucrose
104 of 120
Nucleus
An organelle that contains the cell's genetic information, in the form of DNA, that controls the activities of the cell.
105 of 120
Oesophagus
Part of the gut that carries food from the mouth to the stomach.
106 of 120
Optical Microscope
This uses light rays that pass through lenses to produce a magnified image of an object.
107 of 120
Optimum
This refers to the temperature or pH at which the rate of enzyme activity is highest.
108 of 120
Oral Rehydration Solution
This is a means of treating dehydration by giving a person a drink containing a balanced concentration of salts and glucose, that stimulates the gut to reabsorb water.
109 of 120
Organelle
A membrane-bound structure in the cytoplasm of a cell, eg mitochondria.
110 of 120
Osmosis
The passage of water from a region where there is a higher water potential across a partially permeable membrane.
111 of 120
Passive
A process that does not require energy from ATP
112 of 120
Pathogen
Any microorganism that causes disease
113 of 120
Pellet
A solid layer forming in a test tube after a suspension has been spun in a centrifuge.
114 of 120
Polypeptide
The bond formed when two amino acids join together.
115 of 120
Peristatis
Co-ordinated waves of contraction and relaxation of the smooth muscle making up the gut wall, which propel the gut contents along the digestive tract.
116 of 120
Phagocytosis
Mechanism by which cells engulf particles to form a vesicle or vacuole. E.g. how a macrophage engulf pathogens.
117 of 120
Phospholipid
This is a type of lipid found in the cell membrane. It consists of glycerol with 2 fatty acids and a phosphate group.
118 of 120
Plasmid
A small circle of DNA found in some bacteria. It contains genes additional to those in the main DNA of the cell.
119 of 120
Polymer
Large molecule made of many repeating smaller molecule (monomeres)
120 of 120

Other cards in this set

Card 2

Front

Activation Energy

Back

The minimum amount of kinetic energy needed for a reaction to occur

Card 3

Front

Active Site

Back

Preview of the front of card 3

Card 4

Front

Active Transport

Back

Preview of the front of card 4

Card 5

Front

Aerobic Respiration

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »