Module 4: Classification And Evolution

Question 1

The biological classification of species

Answer 1

• domains (archaea , Eubacteria , Eukarya
• 6 kingdoms ( archaebacteria , protoctista plantae , animalia , fungi , prokaryota )
• phylum
• class
• order
• family
• genus
• species

Reasons for classification : identify species , predict characteristics , find evolutionary links

Question 2

The binomial system of naming species and the advantage of such

Answer 2

• binomial nomenclature
• ( Genus and species ) - used for common language (universal ) , relationships between organisms ( same genus different species , somewhat related)
• written in Latin - italics - underline genus

Question 3

The relationship between classification and phylogeny

Answer 3

Phylogeny - evolutionary relationship between organism- how closely organisms are related - shown in a phylogenetic tree
- shows evolutionary relationships /time - going up the tree means further to the present - continuous

Question 4

The features used to classify organisms into five kingdoms

Answer 4

ANIMALIA - eukaryotic, no cell wall&chloroplasts , multicellular , heterophobic ,nucleus
PLANTS - Eukaryotic, multicellular, cellulose cell wall
Chloroplast, autotrophic
FUNGI- eukaryotic, chitin cell walk no chloroplasts , saprophytic feeders , store food as glycogen
PROKARYOTAE- prokaryotic,unicellular,cells with no nucleus , peptidoglycan cell wall
PROTOTISTA - move using. cilia , flagellum , amoeboid

Question 5

The evidence that led to new classification systems, three domains of life , clarifies relationships

Answer 5

1. Palaeontology- study of fossils - simple lifeforms evolved into complex ones , animals need plants to survive and reproduce (plant fossils formed before animal fossils ) , how closely related organisms might be based on similarity /difference in structure
   - problem - incomplete record , undiscovered
2. Comparative anatomy - homologous structures (same underlying structures)
3. Comparative biochemistry- dna /sequence comparison - important molecules are highly conserved

Question 6

Test for t- test (stats) / spearman’s rank

Answer 6

Standard deviation =a measure of how spread data is
- t- test - compare mean data see if there a SIGNIFICANT DIFFERENCE
-spearman’s rank - find +/- correlation between 2 data sets

• null hypothesis- by chance , random
• do t-test , except/reject null hypothesis
  -critical value greater than t-test /r/s value (there’s a significant difference , accept null ) vise versa

Question 7

The mechanism by which natural selection can affect the characteristics of a population over time

Answer 7

How environment change (natural selection)
, 1. There is pre-existing variation,
2. There’s a section pressure (some individuals survive and some die ) - best adapted individual survive/reproduce
3. Pass in advantageous alley
4. Increase the allele frequency, lots individual have same allele - speciation (new species is formed )
E.g. bacteria- new antibiotics, those will allele can resist antibiotic can be passed on

Question 8

The different types of variation

Answer 8

• interspecific - variation / differences between different species
• intraspecific - variation / differences within a species
• continuous - data is between 2 points - numerical (quantitative) - line graphs
• discontinuous- distinctive groups , quantitative - use bar charts
• causes - genetics ( disorders / blood types / colour) , both ( height , weight , skin colour) environment ( scarring , piercings)

Question 9

Differences in genetics

Answer 9

• different alleles ( dominant/ recessive )
• mutations
  -meiosis ( crossing over) - chromatids swap over
• independent assortment - homologous chromosomes
  -random fertilisation

Question 10

The different types of adaptations of organisms to their environment

Answer 10

• adaptation - specific features in organisms help with survival/ ability to compete with other organisms
• behavioural - e.g. penguin huddle
• anatomical- physical features ( fur , hair , claws ) - evidence (homologous structures ) -analogous- same function/appearance but different underlying structures
• physiological- chemical processes in body ( respiration)
• divergent evolution (2 species evolved from same common ancestor )
• convergent evolution- two species similar adaptations in the same habitat but have different evolutionary origin (analogous)