M1 U2 Biological Molecules

Question 0

Metabolism

Answer 0

Is the sum total of all the biochemical reactions taking place in the cells of an organism

Question 1

A risk factor

Answer 1

Is a factor that increases your chance of developing a particular disease

Question 2

Covalent bonds

Answer 2

Are formed when electrons are shared between atoms. These bonds are very strong. Covalently bonded atoms form new molecules.

Question 3

Carbohydrates

Answer 3

Make up a group of molecules containing carbon, hydrogen and oxygen in the ratio Cn(H2O)n.

Question 4

Polysaccharides

Answer 4

Are polymers of monosaccharides. They consist of hundreds to thousands of monosaccharide monomers bonded together to form a single large molecule.

Question 5

Cellulose

Answer 5

Is a carbohydrate polymer made by bonding many B-glucose molecules together in long chains

Question 6

Amino acids

Answer 6

Are the monomers of all proteins. All amino acids have the same basic structure. The 20 different amino acids involved in protein synthesis differ only in the R-group bonded to the central carbon.

Question 7

The primary structure

Answer 7

Of a protein is given by the specific sequence of amino acids that make up the protein

Question 8

Secondary structure

Answer 8

Refers to the coiling and pleating of parts of the polypeptide molecule

Question 9

Tertiary structure

Answer 9

Refers to the overall 3D structure of the final polypeptide or protein molecule

Question 10

Haemoglobin

Answer 10

Is a globular transport protein

Question 11

Collagen

Answer 11

Is a fibrous structural protein

Question 12

Lipids

Answer 12

Are a diverse group of chemicals that dissolve in organic solvents, such as an alcohol, but not in water. They include fatty acids, triglycerides, and cholesterol.

Question 13

A hydrogen bond

Answer 13

is a weak interaction that can occur wherever molecules contain a slightly negatively charged atom bonded to a slightly positively charged hydrogen. Water molecules hydrogen-bond with each other extensively.

Question 14

Food tests

Answer 14

Are simple tests that show the presence of various biological molecules in samples or structures. Iodine can stain plant tissue sections to show where starch is.

Question 15

A quantitive test

Answer 15

Gives a measure of a substance in units, not simply an indication of its presence.

Question 16

Assay techniques

Answer 16

Are often used to compare measurements with known samples so that quantitive measurements can be made.

Question 17

Nucleotides

Answer 17

Are the monomers of all nucleic acids. Each nucleotide is formed by bonding together a phosphate group, a sugar molecule and a nitrogenous base.

Question 18

DNA

Answer 18

Is a stable polynucleotide molecule. It acts as an information store because the bases projecting from the backbone act as a coded sequence. Organisms differ in their DNA only because they contain different sequences of bases in the DNA.

Question 19

A gene

Answer 19

Is the length of DNA (part of a DNA molecule) that codes for one (or more) polypeptides. Each gene occupies a specific place (locus) on a chromosome. Different versions of the same gene are called alleles.

Question 20

A catalyst

Answer 20

Is defined as a molecule (or element) that speeds up a chemical reaction but does not get used up in the reaction. At the end of the reaction, the catalyst remains unchanged.

Question 21

Extracellular enzymes

Answer 21

Catalyse reactions outside the cell

Question 22

Intracellular enzymes

Answer 22

Catalyse reactions inside the cell

Question 23

Activation energy

Answer 23

Is the amount of energy that must be applied for a reaction to proceed. Different reactions require different levels of activation energy. Enzymes reduce the amount of activation energy needed to allow a reaction to proceed.

Question 24

Denaturation

Answer 24

Changes the tertiary structure of an enzyme such that it cannot function and its function cannot be restored. It does not change the primary structure of an enzyme (or any protein).

Question 25

Optimum pH

Answer 25

Is the pH value at which the rate if an enzyme controlled reaction is at its maximum. Each enzyme has a specific optimum pH.

Question 26

A factor is described as a limiting factor in a situation where,

Answer 26

If all other conditions are kept constant, increasing the concentration of that factor alone will increase the reaction rate.

Question 27

An enzyme inhibitor

Answer 27

Is any substance or molecule that slows down the rate of an enzyme-controlled reaction by affecting the enzyme molecule in some way.

Question 28

A cofactor

Answer 28

Is any substance that must be present to ensure enzyme-controlled reactions take place at the appropriate rate. Some cofactors are part of the enzyme (prosthetic groups); others affect the enzyme on a temporary basis (coenzymes and inorganic ion cofactors).

Question 29

A biosensor

Answer 29

Uses enzyme-controlled reactions to detect the presence of substances in a highly sensitive and specific way. If the substance is present, the enzyme-controlled reaction takes place. The biosensor has a mechanism for revealing whether product is made.

Question 30

A variable

Answer 30

Is any factor that may change and therefore affect the reaction rate. Enzyme investigations require all variables to be controlled.

Question 31

An anomalous result or reading

Answer 31

Is one that looks out if place with other results or readings.

Question 32

The turnover number of an enzyme

Answer 32

Is the number of reactions an enzyme molecule can catalyse in one second. In catalase, the turnover number is up to 200 000