Genetic Material
What is complementary base-pairing?
A with T and C with G
What is a zygote and what process creates it?
A male and a female gamete fuses in the process of fertilization to make a zygote.
Define the law of segregation.
The law of segregation states that the two alleles for a trait or gene segregate (separate) during the phases of meiosis.
What is complete dominance?
complete dominance, one allele is expressed and the other is not.
Describe the process of gel electrophoresis.
Using restriction enzymes cut DNA into fragments. Put the DNA solution into the wells of the electrophoresis gel. Run a current through the gel. This will separate the fragments by size; the shortest ones will travel the furthest.
Define a gene and a chromosome.
Genes are units of inherited information that carry a code for specific traits or functions. A chromosome consists of one long, condensed DNA molecule containing hundreds or thousands of genes
What is non-disjunction and what condition does it lead to?
When homologous chromosomes do not separate during anaphase I or II of meiosis, non-disjunction happens.
It leads to trisomy.
Define genotype and phenotype. Give an example of each.
Genotype is the genetic makeup and phenotype is the expressed traits. Genotypes: Tt and phenotype: tall.
What is incomplete dominance vs co-dominance? Give examples.
incomplete dominance is an inheritance pattern in which the phenotype of a heterozygous individual falls between the two parental phenotypes
A heterozygous offspring of a red snapdragon and a white snapdragon (Ww) will be pink.
codominance, both alleles are completely expressed at the same time.
A red bull and a white cow will have a child with a roan (red & white at the same time) coat.
What is the process of making recombinant DNA (talk about cutting and pasting)?
Remove a desired gene from a DNA molecule using restriction enzymes. Paste the gene into a bacterial plasmid using DNA ligase. This is a recombinant plasmid that can take the new genetic material to any desired location.
What are the 2 types of nitrogenous bases and their exact?
Bases are pyrimidines (single-ringed, T, C) & purines (double-ring, A, G).
What are the phases of mitosis? Briefly describe each.
Prophase: chromosomes condense and nuclear envelope breaks.
Metaphase: chromosomes line up in the center of the cell
Anaphase: spindle fibres pull sister chromatids to opposite poles
Telophase & cytokinesis: cell membrane pinches to break into 2 cells
What is the law of independent assortment?
Mendel’s second law, the law of independent assortment, states that genes that segregate independently in meiosis do not influence each other’s inheritance.
What types of inheritance does blood type express? Name the blood types and their inheritance modes.
A: complete dominance to i.
B: complete dominance to i.
ii: recessive
AB: co-dominant
What is a GMO? How are GMOs important in crop production?
A GMO is any organism that has genetically engineered materials.
Crop production: use genes that target diseases/pests, increase production, better taste, etc.
What is a nucleotide
Deoxyribose sugar, a phosphate, and a nitrogenous base make up a nucleotide.
Define each of the following mutations: translocation, deletion, duplication, inversion.
Translocation: a fragment of one chromosome attaches to a nonhomologous chromosome
Deletion: a chromosome fragment is deleted
Duplication: a chromosome fragment is duplicated
Inversion: 2 chromosome fragments get reversed
What is the difference between homozygous and heterozygous and dominant and recessive?
Homozygous are the same alleles for a gene and heterozygous are different alleles for a gene. A dominant allele determines the phenotype but a recessive allele is not expressed.
What is polygenic inheritance? How does this show up in a population?
A polygenic trait has a range of phenotypes due to the additive effects of multiple genes. It shows up in a range/spectrum of phenotypes.
Describe the process of nuclear transplantation.
The nucleus from an adult cell replaces the nucleus in an egg. If the egg begins to develop into an embryo, it is implanted into a host.
How is DNA packaged?
Histones which DNA coils around → this is a nucleosome. Nucelosomes condense to become chromosomes
List 4 differences between mitosis and meiosis (compare the stages, locations, outcomes, etc).
In meiosis, there are 2 of each phase that’s in mitosis.
Prophase I of meiosis has crossing-over.
Mitosis produces genetically identical cells but meiosis produces unique cells.
Mitosis cells are diploid but meiosis ones are haploid.
Mitosis happens in somatic cells and meiosis in reproductive cells.
What is cross-fertilization and a hybrid?
Cross-fertilization: sperm from the pollen of one plant fertilizes the eggs in the flower of a different plant.
Hybrid: results from 2 true-breeding varieties of the same species.
What is genetic linkage?
The tendency for alleles for different genes on the same chromosome to be inherited together is called genetic linkage. Genes with loci that are close together are known as linked genes.
How does gene therapy happen using a viral vector?
Modified DNA is inserted into a virus vector. The vector binds to the cell membrane as it enters the cell. A vesicle forms around the virus vector as it enters the cell. The vesicle breaks to let it insert its DNA into the host cell. The cell makes proteins using the new gene.