Unit 3 List 1 DNA + Heredity IV

Question 1

adenine

Answer 1

a compound which is one of the four constituent bases of nucleic acids. A purine derivative, it is paired with thymine in double-stranded DNA.

Question 2

amino acid

Answer 2

organic compounds that contain both amino and carboxylic acid functional groups.

Question 3

anticodon

Answer 3

a trinucleotide sequence located at one end of a transfer RNA (tRNA) molecule, which is complementary to a corresponding codon in a messenger RNA (mRNA) sequence.

Question 4

cell type

Answer 4

a classification used to identify cells that share morphological or phenotypical features.

Question 5

cell differentiation

Answer 5

the process in which a stem cell changes from one type to a differentiated one.

Question 6

chromosome

Answer 6

a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

Question 7

codon

Answer 7

a sequence of three DNA or RNA nucleotides that corresponds with a specific amino acid or stop signal during protein synthesis.

Question 8

cytoplasm

Answer 8

the gelatinous liquid that fills the inside of a cell.

Question 9

cytosine

Answer 9

a compound found in living tissue as a constituent base of nucleic acids. It is paired with guanine in double-stranded DNA.

Question 10

deoxyribose

Answer 10

a sugar derived from ribose by replacing a hydroxyl group with hydrogen.

Question 11

DNA (deoxyribonucleic acid)

Answer 11

a self-replicating material that is present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.

Question 12

double helix

Answer 12

a pair of parallel helices intertwined about a common axis, especially that in the structure of the DNA molecule.

Question 13

endoplasmic reticulum

Answer 13

a network of membrane-enclosed tubules and sacs (cisternae) that extends from the nuclear membrane throughout the cytoplasm

Question 14

enzyme

Answer 14

a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction.

Question 15

gene

Answer 15

a distinct sequence of nucleotides forming part of a chromosome, the order of which determines the order of monomers in a polypeptide or nucleic acid molecule which a cell (or virus) may synthesize.

Question 16

golgi apparatus

Answer 16

a complex of vesicles and folded membranes within the cytoplasm of most eukaryotic cells, involved in secretion and intracellular transport.

Question 17

guanine

Answer 17

a compound that occurs in guano and fish scales, and is one of the four constituent bases of nucleic acids. A purine derivative, it is paired with cytosine in double-stranded DNA.

Question 18

hydrogen bond

Answer 18

a weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other.

Question 19

mRNA

Answer 19

(messenger RNA) a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of synthesizing a protein.

Question 20

mutation

Answer 20

the changing of the structure of a gene, resulting in a variant form that may be transmitted to subsequent generations, caused by the alteration of single base units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes.

Question 21

nitrogenous base

Answer 21

nitrogen-containing biological compounds that form nucleosides, which, in turn, are components of nucleotides, with all of these monomers constituting the basic building blocks of nucleic acids.

Question 22

nuclear membrane

Answer 22

made up of two lipid bilayer membranes that in eukaryotic cells surround the nucleus, which encloses the genetic material. The nuclear envelope consists of two lipid bilayer membranes: an inner nuclear membrane and an outer nuclear membrane.

Question 23

nucleic acid

Answer 23

a complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.

Question 24

nucleotide

Answer 24

a compound consisting of a nucleoside linked to a phosphate group. Nucleotides form the basic structural unit of nucleic acids such as DNA.

Question 25

nucleus

Answer 25

the structure in a cell that contains the chromosomes.

Question 26

peptide bond

Answer 26

an amide type of covalent chemical bond linking two consecutive alpha-amino acids from C1 of one alpha-amino acid and N2 of another, along a peptide or protein chain.

Question 27

phosphate group

Answer 27

A functional group characterized by a phosphorus atom bonded to four oxygen atoms

Question 28

polypeptides

Answer 28

A substance that contains many amino acids

Question 29

protein synthesis

Answer 29

a core biological process, occurring inside cells, balancing the loss of cellular proteins through the production of new proteins.

Question 30

ribose

Answer 30

a sugar of the pentose class which occurs widely in nature as a constituent of nucleosides and several vitamins and enzymes.

Question 31

ribosome

Answer 31

a minute particle consisting of RNA and associated proteins found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.

Question 32

RNA (ribonucleic acid)

Answer 32

ribonucleic acid, a nucleic acid present in all living cells. Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins, although in some viruses RNA rather than DNA carries the genetic information.

Question 33

rRNA

Answer 33

(ribosomal RNA) a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes.

Question 34

start codon

Answer 34

the first codon of a messenger RNA transcript translated by a ribosome. The start codon always codes for methionine in eukaryotes and archaea and a N-formylmethionine in bacteria, mitochondria and plastids.

Question 35

stop codon

Answer 35

a codon that signals the termination of the translation process of the current protein.

Question 36

thymine

Answer 36

a compound which is one of the four constituent bases of nucleic acids. A pyrimidine derivative, it is paired with adenine in double-stranded DNA.

Question 37

transcription

Answer 37

the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins produce messenger RNA. Other segments of DNA are transcribed into RNA molecules called non-coding RNAs.

Question 38

translation

Answer 38

the process in living cells in which proteins are produced using RNA molecules as templates. The generated protein is a sequence of amino acids. This sequence is determined by the sequence of nucleotides in the RNA. The nucleotides are considered three at a time.

Question 39

tRNA

Answer 39

(transfer RNA) a type of RNA molecule that helps decode a messenger RNA (mRNA) sequence into a protein.

Question 40

uracil

Answer 40

a nitrogenous base that is a component of RNA. replaces thymine

Question 41

vesicle

Answer 41

a structure within or outside a cell, consisting of liquid or cytoplasm enclosed by a lipid bilayer.