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Flashcards in key terms Deck (31)
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1

disease

condition that impairs normal functioning of an organism

2

pathogens

organism that causes the disease, bacteria fungi virus protoctista

3

communicable disease

disease that can spread between organisms

4

antigens

molecules usually proteins or polysaccharides on surface of cell

5

antibiotics

chemicals that kill or inhibit the growth of bacteria

6

biodiversity

variety of living organism in an area

7

species

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

8

habitat

where an organism lives

9

polymorphism

loud with 2 or more alleles

10

keystone specie

specie on which many other species of an ecosystem depend on

11

taxonomy

the study of classification

12

phylogeny

study of evolutionary history of organisms

13

gene

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

14

allele

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

15

genotype

the allele an organism has eg BB or Bb or bb

16

phenotype

characteristics alleles produce eg blue eyes

17

dominant allele

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

18

recessive allele

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

19

codominant allele

both expressed in phenotype eg alleles for haemoglobin

20

locus

fixed position of a gene on a chromosome

21

homozygote

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

22

heterozygote

an organism that cattier two different alleles eg Bb

23

carrier

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

24

gene pool

complete range of alleles in a population

25

allele frequency

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

26

speciation

development of new species

27

population

all organisms of one specie in an habitat

28

producers

organisms that produce organic molecules using sun light energy eg plants

29

consumers

organism that eats other organisms eg. animals and birds

30

decomposer

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

31

trophic level

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