Evolution and Genetics Flashcards
Taxonomy of being
Domain
Kingdom
Phylum
Class
Order
Family
Species
Genus
Darwins theory of evolution
There is variation within the population (genotype and phenotype)
There are challenges within the environment
Individuals with characteristics that allow them to survive within the environment will live long enough to reproduce and pass on their genes/characteristics to the next generation
These genes will then become prominent in the population
Populations change so much they cannot interbreed with other species-new species are created
Evidence for evolution
Evidence for the theory:
Fossil Records and Geological Strata-
Organisms are eventually fossilized within soil, over time this results in layers of species being fossilized creating a geological stratum, through looking at changes within these fossil layers over time we can observe gradual changes within species providing support for the theory of evolution
Atanomical similarity
-Some species have similarity in atonomy, e.g a bats wing and a cats arm are genetically similar suggesting shared descent. In modern times we can observe some species are highly similar genetically also providing support for the theory.
3) Artificial selection
We can selectively breed animals and plants to have desired species and then we will observe they produce offspring with the same characteristics, this shows species can evolve and change through human intervention.
Genes:
Genes: A sequence of DNA which provide instructions to cells and make proteins important for the function, structure and regulation of bodily functions
Where are genes found
Chromosomes on the nucleus of every cell
How many chromosomes do we have
23 matched pairs, 46 total
How many chromosomes in haploid cells
23
How many chromosomes in diploid cells
46
Haploid Cells:
Cells that only contain 23 pairs of chromosomes, in humans this is in the egg and sperm
-When sperm fertilises the egg, the 23 chromosomes from the mother combine with the 23 from the father
Diploid cells
Every cell but gamete cells-contain 46 chromosomes total
How are haploid cells created
Meiosis
How are diploid cells created
Mitosis-a complete copy of the cell with identical genetic information is created
Alleles
Two corresponding genes within a chromosome pair, we inhereit two alleles from each parent and these determine our genotype and phenotype. can be dominant or recessive
Genome
All 46 cells on the chromosome
Dominant Genes
Only need one copy to be expressed
Recessive Genes:
Need two copies to be expressed, recessive traits may skip a generation from grandparent to offspring
Homozygous Alleles
When we inheret 2 copies of the same gene- e.g AA
Heterozygous Alleles
When they inheret two different versions of a gene, e.g Gy
DNA structure
Double helix made up of two nucleuotide strains-each ribbon is made from a sugar-phosphate backbone with nucleotide bases
Nucleotides
Make up DNA structure, each nucleotide is made from nitrogen containing nucleobases
Adenine [A], Cytosine [C], Guanine [G], or Thymine [T]
What are nucleuotides made up of
Adenine [A], Cytosine [C], Guanine [G], or Thymine [T]
What does adenine pair up with
Thymine
What does cytosine pair up with
Guaninine
How does DNA replicate
through enzymes
Dna strand is unzipped (helicase)
New template strand is primed (primase)
New DNA segment assembled (polymarese)
DNA replication: Helicase
Unzips the dna strand
DNA replication: Primase
Primes new template strand
Polymarese
Assembles new dna segment
