3.4.5 Species and taxonomy (Unit 4 DNA and Relationships) Flashcards
What are the 5 things courtship behaviours allows individuals to do?
- Recognise members of the same species
- Identify a sexually mature mate
- Form a pair bond that will lead to successful mating and raising of offspring
- Synchronise mating so that it takes place at a time where the egg and sperm are most likely to meet
- Become able to breed by bringing a member of the opposite sex into a state that allows breeding to occur
What are the 2 types of classification?
*hierarchy classification
- Phylogenetic classification
What is meant by a hierarchy
smaller groups within larger groups (groups within groups) which DO NOT overlap
Explain what is meant by a phylogenetic relationship
Shows evolutionary relationship
Scientist can use protein structure to investigate the evolutionary relationships between different species. Explain why
The closer the amino acid sequences of 2 organisms the closer their relationship
The amino acid sequence is related to the DNA base triplet sequence
Explain what is meant when 2 species are described as being “closely related”.
They have DNA in common
And they have a recent common ancestor
Explain the principles which biologists use to classify organisms into groups
Large groups are divided into smaller groups
Members of a group have features in common.
Also member of the same group have a similar evolutionary history which is based on fossils
Describe how comparisons of biological molecules in 2 species of sea horses could be used to find out if they are closely related
Compare their DNA by comparing their base sequence
To do this do DNA hybridisation by separating dna strands by breaking the hydrogen bonds
The temperature required to separate the strands indicates how close the 2 species are.
Could also compare the amino acid sequence of the proteins in the 2 species
This is called immunological evidence.
So inject seahorse protein into a rabbit and collect the antibodies the rabbit makes.
Then add the antibody mixture into the other seahorse species blood sample
The amount of precipitate indicates how close the relationship of the 2 sea horses
What 2 measurements would ecologists need to obtain to calculate an index of diversity of a community
1) the number of individuals of EACH species
2) the totals number of individuals of ALL species
A species is
a group of similar organisms capable of breeding and producing fertile offspring
The binomial system consists of..
generic and species name
grouping organisms together is called
classification
The science of classification is called…
taxonomy
How many levels of groups are there in classification?
8
Each group in classification is called a .
taxon
