1.3. Biological molecules (2) - Key words Flashcards
Nucleotides
Molecules with 3 parts - pentose sugar, nitrogen-containing base and a phosphate group joined by condensation reaction
Adenosine Triphosphate (ATP)
Nucleotide that acts as the universal energy supply molecule in cells. It’s made up of the base adenine, ribose and 3 phosphate groups
Purine base
Base found in nucleotides that has 2 nitrogen-containing rings
Pyrimidine base
Base found in nucleotides that has one nitrogen-containing ring
Adenine
Purine base found in DNA + RNA
Guanine
Purine base found in DNA + RNA
Cytosine
Pyrimidine base found in DNA + RNA
Thymine
Pyrimidine base found in DNA
Uracil
Pyrimidine base found in RNA
ATPase
Enzyme that catalyses the formation and breakdown of ATP
Adenosine diphosphate (ADP)
Nucleotide formed when ATP loses a phosphate group and provides energy to drive reactions in the cell
Redox reaction
Reactions in which one reactant loses e- (oxidation) and another gains e- (reduction)
Nucleic acid
Polymer made up of many nucleotide monomer units that carry all the information needed to form new cells
Phosphodiester bond
Bond formed between the phosphate group of one nucleotide and the sugar of the next nucleotide in a condensation reaction
Genome
Entire genetic material of an organism
DNA helicase
Enzyme involved in DNA replication that unzips the two strands of the DNA molecule
DNA polymerase
Enzyme involved in DNA replication that lines up and catalyses the linking up the nucleotides along the template strand
DNA ligase
Enzyme involved in DNA replication that catalyses the formation of phosphodiester bonds between the two strands of DNA
Translation
Process by which proteins are produced, via RNA, using the genetic code found in the DNA. Takes place on the ribosomes
Ribosomes
Site of protein synthesis in the cell
Triplet code
Code of 3 bases, and is the basis of the genetic info in the DNA
Gene
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
Codon
Sequence of 3 bases in DNA or mRNA
Complementary strand
Strand of RNA formed that complements the DNA acting as the coding strand
mRNA
RNA formed in the nucleus that carries the genetic code out into the cytoplasm
Antisense strand
Template strand
DNA strand that codes for proteins
DNA-directed RNA polymerase
RNA polymerase
Enzyme that polymerises nucleotide units to form RNA in a sequence determined by the antisense strand of DNA
tRNA
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
Anticodon
Sequence of 3 bases on tRNA that are complementary bases in the mRNA codon
rRNA
RNA that makes up about 50% of the structure of the ribosome
Polysomes
Groups of ribosomes, joined by a thread of mRNA, that can produce large quantities of a particular protein
Sense strand
Has the same base sequence as the mRNA transcribed from the antisense strand
Mutation
Permanent change in the DNA of an organism
Gametes
Haploid cells produces by meiosis that fuse to form a new diploid cell in sexual reproduction
Point (gene) mutation
Change in one or a small number of nucleotides affecting a single gene
Substitution
Type of point mutation in which one base in a gene is substituted for another
Deletion
Type of point mutation in which one base in a gene is deleted
Insertion
Type of point mutation in which one base in a gene is added
Chromosomal mutation
Changes in the position of entire genes within a chromosome
Whole-chromosome mutation
Loss or duplication of a whole chromosome
Sickle cell disease
Human genetic disease affecting the protein chains making up the haemoglobin in the red blood cells
Mutagen
Anything that increases the rate of a mutation
