Evolution Flashcards
Name and explain the hierarchy of classification
Kingdom, phylum, class, order, family, genus, species. It is a type of taxonomy, and was created by Carl Linnaeus. In this system each level down from kingdom becomes more similar to each other, until you reach the species level where organisms are most specific.
What are cladograms?
Cladograms represent the similarities and differences between species. It shows where specific traits arose in the evolutionary tree.
Define species
A group of species is defined as a group or organisms that closely resemble each other and can interbreed to produce fertile offspring
What are the writing rules of Carl Linnaeus’ binomial system of nomenclature?
You write their genus then species
1. Genus name must be capitalised, however species name lower case
2. Both words must be italicised when typed and underlined when written.
E.g. Home sapien
Why do we use Latin to name species? And why do we use common names?
- Latin is a dead language, which means the meanings of the words don’t change
- It helps to create a universal language for all biologists to use
- Latin words are descriptive and can therefore be used to tell us something about the organism
Latin names or difficult to pronounce, so we use use common names
E.g. Saltwater crocodile
Name the four different types of homos (man) and describe their species name
Homo habilis - skilful
Homo erectus - upright
Homo neanderthalensis - name offer the neander valley where they were first found
Homo sapiens - wise, rational
Define population, community and ecosystem
Population - a group of organism of the same species living in a particular area at a particular time
Community - all the biotic and abiotic factors living in an area at the same time
Ecosystem - all the abiotic and biotic components and the interaction between them
Name the hierarchy of an ecosystem?
Organism, species, population, community, ecosystem
Explain biodiversity
Biodiversity can be described as a variation within living things, in terms of an ecosystem. There are two types:
- Species diversity
- Genetic diversity
Why do biologist classify?
- information is easier to handle
- more effective communication and understanding about a group
- allows prediction of behaviour or characteristics of a group member
Differentiate between genetic diversity and species diversity. What category do they fall under?
Genetic diversity refers to for example, the range of genetic characteristics within a single species e.g. Blue, green, brown eyes. Species diversity refers to the number of different species in an ecosystem e.g. Fish, corals, sharks, in an ecosystem.
They fall under biodiversity
Explain mutations
Mutations are a source of new genetic variation. A change in the genetic code in DNA can lead to a change in protein that is coded for and produced by that segment of DNA. Mutations that occur in gametes are the source of new alleles within populations.
Name the three types of mutations
- Addition/Insertion
- Deletion
- Substitution
What is addition/insertion ? And what is the difference between frameshift and non-frameshift?
Addition occurs when a nucleotide(s) are added into the DNA sequence which leads to a change in the genetic code. Frameshift is insertion of a number of nucleotides which are not divisible by three whereas non-frameshift is insertion of a number of nucleotides divisible by three.
What is deletion?
Deletion occurs when nucleotide(s) are deleted in a DNA sequence causing a change in the genetic code. Deletion can also be either frameshift or non-frameshift.
What is substitution?
Substitution occurs when nucleotide(s) are directly replaced in the DNA sequence, causing a change in the genetic code. However no frameshift mutation is possible for substitution mutations.
Explain meiosis
Meiotic divisions lead to production of gametes. During replication, crossing over of genetic information in chromosomes leads to high genetic variability in resulting daughter cells, thus no two gametes are the same.
