DNA and Genes
What are the base pairings for nitrogenous bases
A-T and G-C
The first phase of Meiosis 1 is called:
Prophase 1
A persons genotype for hair colour is represented by Hh. What type of genotype is this?
Heterozygous
The changing of allele frequency within a population over time is an example of which type of evolution
Microevolution
In Cladogams, the point at which one species separates from another is also known as a ______
Node
Another name for non-coding genes is ________
Introns
A ___________ is a display of the total complement of an organisms chromosomes
Karyotype
Define speciation
The evolutionary process by which new, distinct species are formed
Scientists analysed a strand of DNA from 3 different species to identify which species (out of B and C) are least related to species A. Species B had 4 differences in the nucleotide sequence compared to Species A, and Species C had 7 differences in the nucleotide sequence compared to Species A. Which one is least related to Species A?
Species C
In Protein Synthesis, transcription happens where in the cell
Nucleus
A point mutation is a change in a single nucleotide in the DNA code. Which type of point mutation results in one amino acid being substituted for another
Missense
What type of punnet square is done when you have to take into account two different traits instead of one (eg hair colour and eye colour)
Dihybrid cross
Hummingbirds with longer beaks have easier access to eat nectar within flowers. As generations progress, flowers with deeper petals have become more favourable. Hummingbirds continued to evolve to have even longer beaks, and then flowers again evolved to have even deeper petals. What type of evolution is this.
Coevolution
Species A and D share one common ancestor, and Species A and B share 3 common ancestors. Which species is more closely related to Species A?
Species D
What does DNA helicase do in DNA replication?
Breaks down the weak hydrogen bonds holding the two strands of DNA. Or 'unzips' the DNA
The process of homologous chromosomes failing to separate during Meiosis is called:
Non-disjunction
Blue eyes are dominant to Brown eyes. A woman with Brown eyes has 4 children with a man who has Blue eyes. 2 children have Blue eyes, and 2 have Brown. What genotype does the father have?
Bb - Heterozygous
Over multiple generations, Giraffes evolved to have longer necks due to it being a more favourable trait. What type of phenotypic selection is this
Directional selection
Explain how episodes of mass extinctions lead to evolutionary radiation
Mass extinctions lead to more resources, such as food and space, becoming available to species that once did not have as much access. This newfound room to grow creates more possibilities for mutations and adaptations to occur, leading to vast episodes of evolution
The process known as "tightening" DNA around histone proteins to block transcription
DNA Methylation
In gametogenesis, how many sperm cells are left at the end of spermatogenesis and how many egg cells are left at the end of oogenesis
4 and 1
Haemophilia is an X-linked recessive trait. A woman who is homozygous dominant for the Haemophilia gene has children with a man that has Haemophilia. What are the odds that they will have a girl that has haemophilia.
0%
Describe fecundity
The number of offspring an organism can produce
In Cladograms, define what a 'Clade' is
A Clade is a group of organisms that includes a common ancestor and all its descendants