key terms

Question 1

disease

Answer 1

condition that impairs normal functioning of an organism

Question 2

pathogens

Answer 2

organism that causes the disease, bacteria fungi virus protoctista

Question 3

communicable disease

Answer 3

disease that can spread between organisms

Question 4

antigens

Answer 4

molecules usually proteins or polysaccharides on surface of cell

Question 5

antibiotics

Answer 5

chemicals that kill or inhibit the growth of bacteria

Question 6

biodiversity

Answer 6

variety of living organism in an area

Question 7

species

Answer 7

group of similar organisms that are able to reproduce to give fertile offspring

Question 8

habitat

Answer 8

where an organism lives

Question 9

polymorphism

Answer 9

loud with 2 or more alleles

Question 10

keystone specie

Answer 10

specie on which many other species of an ecosystem depend on

Question 11

taxonomy

Answer 11

the study of classification

Question 12

phylogeny

Answer 12

study of evolutionary history of organisms

Question 13

gene

Answer 13

a sequence of DNA bases that codes for a protein and results in a characteristic eg eye colour

Question 14

allele

Answer 14

different version of a gene, most animals have 2 alleles of each gene one maternal and one paternal, bases in each allele are slightly different, code for different version of the same characteristic represented by letters eg allele brown eyes: B allele blue eyes: b

Question 15

genotype

Answer 15

the allele an organism has eg BB or Bb or bb

Question 16

phenotype

Answer 16

characteristics alleles produce eg blue eyes

Question 17

dominant allele

Answer 17

characteristics appear in phenotype even when there is only one copy, represented by capital letter

Question 18

recessive allele

Answer 18

characteristics appear in phenotype only of two copies are present, eg bb

Question 19

codominant allele

Answer 19

both expressed in phenotype eg alleles for haemoglobin

Question 20

locus

Answer 20

fixed position of a gene on a chromosome

Question 21

homozygote

Answer 21

an organism that carries two copies of the same allele eg BB or bb

Question 22

heterozygote

Answer 22

an organism that cattier two different alleles eg Bb

Question 23

carrier

Answer 23

an organism carrying an allele that is not expressed in their phenotype but that can be passed on to offspring.

Question 24

gene pool

Answer 24

complete range of alleles in a population

Question 25

allele frequency

Answer 25

how often al allele occurs given in percentage 35% or 0.35

Question 26

speciation

Answer 26

development of new species

Question 27

population

Answer 27

all organisms of one specie in an habitat

Question 28

producers

Answer 28

organisms that produce organic molecules using sun light energy eg plants

Question 29

consumers

Answer 29

organism that eats other organisms eg. animals and birds

Question 30

decomposer

Answer 30

organism that breaks down dead or undigested organic material eg bacteria and fungi

Question 31

trophic level

Answer 31

a stage in a food chain occupied by a particular group of organisms, producers are the first trophic level in a food chain.