Kapitel 1

Question 1

Organic molecule containing both an amino group and a carboxyl group. Those that serve as building blocks of proteins are alpha amino acids - having both the amino and carboxyl groups linked to the same carbon atom. (NH2CHRCOOH - Panel 3–1 - pp. 112–113)

Answer 1

amino acid

Question 2

Single-celled organism without a nucleus - superficially similar to bacteria. At a molecular level - more closely related to eukaryotes in genetic machinery than are bacteria. Archaea and bacteria together make up the prokaryotes. (Figure 1–17)

Answer 2

archaeon (plural arch[a]ea) (archaebacterium)

Question 3

Member of the domain bacteria - one of the three main branches of the tree of life (archaea - bacteria - and eukaryotes). Bacteria and archaea both lack a distinct nuclear compartment - and together comprise the prokaryotes. (Figure 1–17)

Answer 3

bacterium (plural bacteria) (eubacterium)

Question 4

Process by which a copy of a DNA molecule is made.

Answer 4

DNA replication

Question 5

Protein that catalyzes a specific chemical reaction.

Answer 5

enzyme

Question 6

Organism composed of one or more cells that have a distinct nucleus. Member of one of the three main divisions of the living world - the other two being bacteria and archaea. (Figure 1–17)

Answer 6

eukaryote

Question 7

Region of DNA that is transcribed as a single unit and carries information for a discrete hereditary characteristic - usually corresponding to (1) a single protein (or set of related proteins generated by variant post-transcriptional processing) - or (2) a single RNA (or set of closely related RNAs).

Answer 7

gene

Question 8

The set of genes in an organism related in DNA sequence due to their derivation from the same ancestor.

Answer 8

gene family

Question 9

One of two or more genes that are similar in sequence as a result of derivation from the same ancestral gene. The term covers both orthologs and paralogs. (Figure 1–21) See homologous chromosomes.

Answer 9

homolog

Question 10

A species that has been studied intensively over a long period and thus serves as a “model” for deriving fundamental biological principles.

Answer 10

model organism

Question 11

Nucleoside with one or more phosphate groups joined in ester linkages to the sugar moiety. DNA and RNA are polymers of nucleotides. (Panel 2–6 - pp. 100–101)

Answer 11

nucleotide

Question 12

Genes or proteins from different species that are similar in sequence because they are descendants of the same gene in the last common ancestor of those species. Compare paralogs. (Figure 1–21)

Answer 12

orthologs

Question 13

Genes or proteins that are similar in sequence because they are the result of a gene duplication event occurring in an ancestral organism. Those in two different organisms are less likely to have the same function than are orthologs. Compare orthologs. (Figure 1–21)

Answer 13

paralogs

Question 14

Linear polymer of amino acids. Proteins are large polypeptides - and the two terms can be used interchangeably. (Panel 3–1 - pp. 112–113)

Answer 14

polypeptide

Question 15

Single-celled microorganism whose cells lack a well-defined - membrane-enclosed nucleus. Either a bacterium or an archaeon. (Figure 1–17)

Answer 15

prokaryote

Question 16

The major macromolecular constituent of cells. A linear polymer of amino acids linked together by peptide bonds in a specific sequence. (Figure 3–1)

Answer 16

protein

Question 17

Polymer formed from covalently linked ribonucleotide monomers. (Figure 6–4)

Answer 17

RNA (ribonucleic acid)

Question 18

Copying of one strand of DNA into a complementary RNA sequence by the enzyme RNA polymerase. (Figure 6–1)

Answer 18

transcription (DNA transcription)

Question 19

Process by which the sequence of nucleotides in an mRNA molecule directs the incorporation of amino acids into protein. Occurs on a ribosome. (Figure 6–64)

Answer 19

translation (RNA translation)

Question 20

Particle consisting of nucleic acid (RNA or DNA) enclosed in a protein coat and capable of replicating within a host cell and spreading from cell to cell. (Figure 23–11)

Answer 20

virus