1.3. Biological molecules (2) - Key words

Question 1

Nucleotides

Answer 1

Molecules with 3 parts - pentose sugar, nitrogen-containing base and a phosphate group joined by condensation reaction

Question 2

Adenosine Triphosphate (ATP)

Answer 2

Nucleotide that acts as the universal energy supply molecule in cells. It’s made up of the base adenine, ribose and 3 phosphate groups

Question 3

Purine base

Answer 3

Base found in nucleotides that has 2 nitrogen-containing rings

Question 4

Pyrimidine base

Answer 4

Base found in nucleotides that has one nitrogen-containing ring

Question 5

Adenine

Answer 5

Purine base found in DNA + RNA

Question 6

Guanine

Answer 6

Purine base found in DNA + RNA

Question 7

Cytosine

Answer 7

Pyrimidine base found in DNA + RNA

Question 8

Thymine

Answer 8

Pyrimidine base found in DNA

Question 9

Uracil

Answer 9

Pyrimidine base found in RNA

Question 10

ATPase

Answer 10

Enzyme that catalyses the formation and breakdown of ATP

Question 11

Adenosine diphosphate (ADP)

Answer 11

Nucleotide formed when ATP loses a phosphate group and provides energy to drive reactions in the cell

Question 12

Redox reaction

Answer 12

Reactions in which one reactant loses e- (oxidation) and another gains e- (reduction)

Question 13

Nucleic acid

Answer 13

Polymer made up of many nucleotide monomer units that carry all the information needed to form new cells

Question 14

Phosphodiester bond

Answer 14

Bond formed between the phosphate group of one nucleotide and the sugar of the next nucleotide in a condensation reaction

Question 15

Genome

Answer 15

Entire genetic material of an organism

Question 16

DNA helicase

Answer 16

Enzyme involved in DNA replication that unzips the two strands of the DNA molecule

Question 17

DNA polymerase

Answer 17

Enzyme involved in DNA replication that lines up and catalyses the linking up the nucleotides along the template strand

Question 18

DNA ligase

Answer 18

Enzyme involved in DNA replication that catalyses the formation of phosphodiester bonds between the two strands of DNA

Question 19

Translation

Answer 19

Process by which proteins are produced, via RNA, using the genetic code found in the DNA. Takes place on the ribosomes

Question 20

Ribosomes

Answer 20

Site of protein synthesis in the cell

Question 21

Triplet code

Answer 21

Code of 3 bases, and is the basis of the genetic info in the DNA

Question 22

Gene

Answer 22

Sequence of bases on a DNA molecule. It contains coding for a sequence of amino acids in a polypeptide chain that affect a characteristic in the phenotype of the organism

Question 23

Codon

Answer 23

Sequence of 3 bases in DNA or mRNA

Question 24

Complementary strand

Answer 24

Strand of RNA formed that complements the DNA acting as the coding strand

Question 25

mRNA

Answer 25

RNA formed in the nucleus that carries the genetic code out into the cytoplasm

Question 26

Antisense strand

Answer 26

Template strand | DNA strand that codes for proteins

Question 27

DNA-directed RNA polymerase | RNA polymerase

Answer 27

Enzyme that polymerises nucleotide units to form RNA in a sequence determined by the antisense strand of DNA

Question 28

tRNA

Answer 28

Small units of RNA that pick up particular amino acids from the cytoplasm and transport them to the surface of the ribosome to align with the mRNA

Question 29

Anticodon

Answer 29

Sequence of 3 bases on tRNA that are complementary bases in the mRNA codon

Question 30

rRNA

Answer 30

RNA that makes up about 50% of the structure of the ribosome

Question 31

Polysomes

Answer 31

Groups of ribosomes, joined by a thread of mRNA, that can produce large quantities of a particular protein

Question 32

Sense strand

Answer 32

Has the same base sequence as the mRNA transcribed from the antisense strand

Question 33

Mutation

Answer 33

Permanent change in the DNA of an organism

Question 34

Gametes

Answer 34

Haploid cells produces by meiosis that fuse to form a new diploid cell in sexual reproduction

Question 35

Point (gene) mutation

Answer 35

Change in one or a small number of nucleotides affecting a single gene

Question 36

Substitution

Answer 36

Type of point mutation in which one base in a gene is substituted for another

Question 37

Deletion

Answer 37

Type of point mutation in which one base in a gene is deleted

Question 38

Insertion

Answer 38

Type of point mutation in which one base in a gene is added

Question 39

Chromosomal mutation

Answer 39

Changes in the position of entire genes within a chromosome

Question 40

Whole-chromosome mutation

Answer 40

Loss or duplication of a whole chromosome

Question 41

Sickle cell disease

Answer 41

Human genetic disease affecting the protein chains making up the haemoglobin in the red blood cells

Question 42

Mutagen

Answer 42

Anything that increases the rate of a mutation