Topic 4 Definitions

Question 1

What is an adaptation?

Answer 1

A feature increasing survival chance in an environment

Question 2

What is an allele?

Answer 2

A version of a gene

Question 3

What is an anticodon?

Answer 3

tRNA nucleotide sequence specific to an mRNA codon

Question 4

What is the arithmetic mean?

Answer 4

The average of a set of numbers

Question 5

What is artificial classification?

Answer 5

Grouping organisms by analogous characteristics

Question 6

What is the binomial system?

Answer 6

Universal naming system with generic and specific names

Question 7

What is biodiversity?

Answer 7

Variety of genes

Question 8

What is a cellular proteome?

Answer 8

Proteins expressed in a cell type

Question 9

What is a chromatid?

Answer 9

One strand of a replicated chromosome

Question 10

What is a chromosome?

Answer 10

DNA and protein structure passing genetic information

Question 11

What is a chromosome mutation?

Answer 11

Change in chromosome number or structure

Question 12

What is classification?

Answer 12

Organizing organisms into groups

Question 13

What is a codon?

Answer 13

mRNA base sequence coding for an amino acid

Question 14

What is conservation?

Answer 14

Maintaining ecosystems and biodiversity

Question 15

What is courtship?

Answer 15

Behavior for selecting reproductive partners

Question 16

What is crossing over?

Answer 16

Exchange of alleles in meiosis 1

Question 17

What does degenerate mean (genetic code)?

Answer 17

More than one triplet codes for an amino acid

Question 18

What is deletion (gene mutation)?

Answer 18

Removal of nucleotide bases from DNA

Question 19

What is directional selection?

Answer 19

Selection favoring individuals differing from the mean

Question 20

What is ecosystem diversity?

Answer 20

Range of different habitats

Question 21

What is eukaryotic DNA?

Answer 21

Linear DNA forming chromosomes with histones

Question 22

What is an exon?

Answer 22

DNA sequence coding for an amino acid sequence

Question 23

What is fertilisation?

Answer 23

Fusion of haploid gametes to form a diploid zygote

Question 24

What is a gene?

Answer 24

DNA length coding for polypeptides and functional RNA

Question 25

What is a gene mutation?

Answer 25

Change in nucleotide bases in DNA

Question 26

What is the generic name?

Answer 26

Organism's genus

Question 27

What is the genetic code?

Answer 27

Rules coding DNA base sequence for amino acid sequence

Question 28

What is genetic diversity?

Answer 28

Number of different alleles in a population

Question 29

What is a genome?

Answer 29

Entire set of genes in a cell

Question 30

What are histones?

Answer 30

Proteins forming chromosomes with DNA

Question 31

What are homologous chromosomes?

Answer 31

Chromosome pair with same gene loci

Question 32

What is independent segregation?

Answer 32

Random separation of chromosomes in meiosis 1

Question 33

What is the index of diversity (d)?

Answer 33

Relationship between species number and abundance

Question 34

What is an intron?

Answer 34

Non-coding DNA sequence

Question 35

What is a locus?

Answer 35

Gene position on a chromosome

Question 36

What is the mean (normal distribution curve)?

Answer 36

Maximum height of a normal distribution curve

Question 37

What is meiosis?

Answer 37

Cell division producing haploid gametes

Question 38

What is mRNA?

Answer 38

RNA carrying genetic information to ribosomes

Question 39

What is mitosis?

Answer 39

Cell division producing identical diploid cells

Question 40

What is a mutagenic agent?

Answer 40

Agent increasing gene mutation rate

Question 41

What is natural selection?

Answer 41

Increased frequency of advantageous alleles

Question 42

What is a non-coding sequence?

Answer 42

DNA sequence not coding for amino acids

Question 43

What is non-disjunction?

Answer 43

Failure of chromosomes to separate in meiosis

Question 44

What does non-overlapping mean (genetic code)?

Answer 44

Each base is read once and part of one triplet

Question 45

What is phylogenetic classification?

Answer 45

Grouping organisms by evolutionary relationships

Question 46

What is phylogeny?

Answer 46

Evolutionary relationships between organisms

Question 47

What is prokaryotic DNA?

Answer 47

Circular DNA without associated proteins

Question 48

What is random sampling?

Answer 48

Sampling technique to avoid bias

Question 49

What is recombination?

Answer 49

Chromatid pieces combining during crossing over

Question 50

What are ribosomes?

Answer 50

Structures for protein synthesis

Question 51

What is RNA polymerase?

Answer 51

Enzyme forming pre-mRNA from DNA template

Question 52

What is a species?

Answer 52

Group of organisms producing fertile offspring

Question 53

What is species diversity?

Answer 53

Number and abundance of different species

Question 54

What is species richness?

Answer 54

Number of different species

Question 55

What is the specific name?

Answer 55

Organism's species

Question 56

What is splicing?

Answer 56

Removal of introns and joining of exons in pre-mRNA

Question 57

What is stabilising selection?

Answer 57

Selection favoring individuals close to the mean

Question 58

What is standard deviation (normal distribution curve)?

Answer 58

Width of a normal distribution curve

Question 59

What is substitution (gene mutation)?

Answer 59

Exchanging one nucleotide base for another

Question 60

What is a taxon?

Answer 60

Group within a phylogenetic classification system

Question 61

What is transcription?

Answer 61

Formation of pre-mRNA or mRNA from DNA template

Question 62

What is tRNA?

Answer 62

RNA carrying amino acids to ribosomes

Question 63

What is translation?

Answer 63

mRNA template for tRNA and polypeptide formation

Question 64

What is a triplet?

Answer 64

Three bases coding for an amino acid

Question 65

What does universal mean (genetic code)?

Answer 65

Code is the same in almost all organisms

Question 66

What is variation?

Answer 66

Differences between individuals