biodiversity

Question 1

define biodiversity

Answer 1

the number of species and the number of individuals of each species in one community

Question 2

species richness

Answer 2

number of different species in a community

Question 3

community

Answer 3

all the individuals of all the species living together in the same area at the same time

Question 4

species

Answer 4

group of similar organisms with the same genes
that reproduce to produce a fertile offspring

Question 5

genetic diversity

Answer 5

difference in DNA base sequences

Question 6

niche

Answer 6

an organism’s role in the ecosystem; how it interacts with other species and responds to the environment
(No 2 species occupy the same niche due to inTERspecific competition)

Question 7

habitat

Answer 7

place where organism usually lives in an ecosystem

Question 8

diversity index

Answer 8

d= N(N-1) / Σ n(n-1)
- answer 2dp
- higher value = greater diversity

d: species diversity index
N: total number of organisms of all species
n: total number of organisms of each species
Σ: sum of

Question 9

what information is required to calculate an index of diversity?

Answer 9

• number of species
• number of individuals in each species

Question 10

the number of species present is one way to measure biodiversity. explain why an index of diversity may be a more useful measure of biodiversity.

Answer 10

• also measures number of individuals in a species
• some species may be present in low/high numbers

Question 11

give 2 advantages of using an index of biodiversity rather than an indicator species

Answer 11

• you do not need to identify each species
• index considers number of organisms of each species

Question 12

suggest one economic argument for maintaining biodiversity

Answer 12

• pharmaceutical uses
• commerical products
• agriculture
• tourism
• svaing local forest communities

Question 13

farming

Answer 13

• reduces species diversity
• natural plants and animals lost when land cleared
• reduces variety of food sources for habitats
• growth of specific crops controlled
• pesticides and herbicides

Question 14

a forest was cleared tk maje more land available for agriculture. After the forest was cleared the species diversity of insects in the area decreased. explain why.

Answer 14

• decrease in variety of plants
• fewer habitats
• decrease in variety of food
• clearing forest kills insects via pesticides, machinery

Question 15

farmers clear tropical forests and grow crops instead. explain how this causes the diversity of insects in the area to decrease

Answer 15

• lower diversity of plants
• fewer sources of food
• few habitats
• fewer herbivores so few carnivores
• agriculture involves killing insects via pesticides

Question 16

classification

Answer 16

grouping of organisms

Question 17

taxonomy

Answer 17

theory and practice of classification

Question 18

define species

Answer 18

group of siilar organisms able to reproduce and form a fertile offspring

Question 19

binomial naming system

Answer 19

• universal
• latin/greek names
  first: Genus
  second: species
• written in italics or underlines
• genus with capital letter
  eg: Homo sapien

Question 20

classification system info

Answer 20

• placed into taxa (groups) based on shared characteristics
• 8 levels of taxa
• forms a hierarchy: groups are contained within larger groups
• no overlap, only belong to one taxon

Question 21

why is the classification system classed as a hierarchy

Answer 21

groups are contained within larger groups

Question 22

archaea domain

Answer 22

• single celled prolaryotes
• genes are similar to eukaryotes
• ether bonds instead of ester in triglycerides
• no murein in cell walls
• more complex RNA polymerase

Question 23

bacteria domain

Answer 23

• no membrane bound organelles (eg: no mitochondria, golgi, RER)
• smaller ribosomes. 70s
• murein cell wall
• circular DNA

Question 24

CLASSIFICATION ORDER

Answer 24

domain
kingdom
phylum
class
order
family
genus
species

Question 25

name the taxonomic group between order and genus

Answer 25

family

Question 26

explain what is meant by a hierarchy

Answer 26

groups within groups no overlap

Question 27

explain what is meant by a phylogenetic group

Answer 27

- grouped according to evolutionary history/common ancestors

Question 28

courtship behaviour

Answer 28

- genetically determined - more clsoely related organisms present same behaviour - attract mate of right species and right sex

Question 29

give five ways in which courtship behaviour increases the probability of successful mating

Answer 29

- attracts same species - attracts opposite sex - indication of sexual maturity - stimulates release of gametes - form pair bond

Question 30

modern classification systems

Answer 30

- use the frequency of observable characteristics - base sequence of DNA/mRNA - SIMILARITIES in genome - amino acid sequence of the proteins coded by DNA and mRNA

Question 31

in classification, comparing the base sequence of a gene provides more information than comparing the amino acif sequence for the gene codes. explain why

Answer 31

- more bases than amino acids - introns - DNA code is degenerate

Question 32

comparing the base sequence of genes provides more evolutionary information than comparing the structure of proteins. explain why,

Answer 32

- introns - degenerate DNA code - more bases than amino acids

Question 33

give 2 ways doctors could use base sequences to compare different types of HPV

Answer 33

- compare DNA base sequence - compare mRNA base sequence - look for mutationa

Question 34

describe how comparisons of biological molecules in 2 species could be used to idetify if theyre closely related

Answer 34

- compare DNA base sequence - compare RNA base sequence - DNA hybridisation to break Hydrogen bonds, temperature required to separate strands indicates relationship - genetic variation - compare sequence of nucleotides and amino acifds - compare mitochondria - obtain antibodies, amount of precipitate indicates relationship

Question 35

explain how natural selection produces changes within a species

Answer 35

- variation due to mutation - predation results in differential survival - soem have better adaptations for survival - differential reproducite success - pass on advantageous alleles - changes allelic frequencies

Question 36

scientists' analysis of blood proteins indicated a lack of genetic diversit in populations of some organisms. describe the processes that lead to a reduction of the genetic diversity of populations of organisms

Answer 36

- reduces numver of different alleles - founder effect - few individuals from the population become isolates - genetic bottlenecks - significant fall in size of population - selective breeding - using organissm with particular phenotype/traits

Question 37

scientists can use protein structure to investigate the evolutionary relationships between different species

Answer 37

- amino acid sequence/ primary structure - closer the amino acid sequence the closer the relationship - protein structure related to DNA base sequence

Question 38

what is meant by genetic bottleneck

Answer 38

- sudden decrease in population by an event (eg: earthquake) - reduced genetic diversity - smaller gene pool

Question 39

suggest one ethical argument for maintaining biodiversity

Answer 39

- prevent extinction - prevents loss of habitats