📘 Chapter 5 Flashcards (DNA, Chromosomes, and Cell Cycle)

adenine/adenosine

a purine nitrogenous base in DNA and RNA that pairs with thymine (or uracil in RNA)

antiparallel

the orientation of DNA strands running in opposite directions (5' to 3' and 3' to 5')

base pair

a pair of complementary nitrogenous bases connected by hydrogen bonds (A-T or G-C in DNA)

cell cycle

the series of stages a cell goes through to grow and divide (G1, S, G2, M)

centromere

the region on a chromosome where sister chromatids are held together and spindle fibers attach

chromatin

complex of DNA and proteins that forms chromosomes in the nucleus

chromosome

a single, long DNA molecule coiled and packaged with proteins, carrying genetic information

complementary

describes the matching base pairing between strands of DNA or RNA (A-T, G-C)

cytosine/cytidine

a pyrimidine nitrogenous base that pairs with guanine in DNA and RNA

deoxyribonucleic acid (DNA)

the molecule that stores genetic information, made of nucleotides with deoxyribose sugar

deoxyribose

the five-carbon sugar found in DNA nucleotides

double helix

the twisted-ladder shape of DNA formed by two antiparallel strands

G1 phase

the first gap phase in the cell cycle where the cell grows and prepares for DNA synthesis

G2 phase

the second gap phase where the cell prepares for mitosis after DNA replication

gene

a sequence of DNA that codes for a specific protein or functional RNA

genome

the complete set of genetic material in an organism

guanine/guanosine

a purine nitrogenous base that pairs with cytosine in DNA and RNA

interphase

the phase of the cell cycle between divisions (includes G1, S, and G2 phases)

karyotype

a visual display of an individual's complete set of chromosomes

M phase

the phase of the cell cycle that includes mitosis and cytokinesis

mitosis

the division of a eukaryotic cell’s nucleus into two identical nuclei

mitotic chromosome

the highly condensed form of chromosomes seen during mitosis

nitrogenous base

a nitrogen-containing molecule (A, T, G, C, U) that forms part of a nucleotide

nucleoside/nucleotide

nucleoside is a base plus sugar

nucleotide is a base, sugar, and phosphate group

origin of replication

a specific DNA sequence where replication begins

phosphate

a molecule involved in nucleotide structure and phosphodiester bonds in DNA/RNA

phosphodiester backbone

the sugar-phosphate chain that forms the structural framework of DNA and RNA

purine

a double-ringed nitrogenous base (adenine and guanine)

pyrimidine

a single-ringed nitrogenous base (cytosine, thymine, uracil)

ribonucleic acid (RNA)

a single-stranded molecule involved in coding, decoding, regulation, and expression of genes

ribose

the sugar found in RNA nucleotides

S phase

the phase of the cell cycle during which DNA is replicated

telomere

the repetitive DNA sequence at the ends of chromosomes that protects them from degradation

thymine/thymidine

a pyrimidine nitrogenous base in DNA that pairs with adenine

uracil/uridine

a pyrimidine nitrogenous base in RNA that replaces thymine and pairs with adenine