How can you tell if a situation is demonstrating a complete dominance pattern for inheritance?
The heterozygote will have the parent phenotype with the stronger allele.
The following karyotype shows the number of chromosomes in a diploid cell. How many chromosomes are there?
44
A squirrel egg cell contains 20 chromosomes. How many chromosomes would a squirrel skin cell contain?
40 (diploid)
When does a gene mutation occur?
DNA replication
Why are the chromosomes in this karyotype X shaped?
They are sister chromatids formed AFTER DNA is replicated.
Abby has type AB blood. What are the POSSIBLE genotypes for her parents? EXPLAIN.
AA, AO, BB, BO, AB---one parent donated an A and the other parent donated a B
Give an example of a trait.
Hair color, eye color, height, etc.
What is a genotype?
The combination of letter alleles donated from each parent that determine's an organisms phenotype for a particular trait.
How is a chromosome related to a chromatid?
Chromosomes that are copied form sister chromatids--they are identical arms of a chromosome.
What is a gamete?
A sex cell produced from meiosis (sperm or egg)
How many chromosomes do haploid human cells contain?
23
heterozygous
genotype with two different types of alleles
What are homologous chromosomes?
chromosomes that are the same size and contain the same genes
How are gametes formed?
Meiosis
Abby has type AB blood. What are the POSSIBLE genotypes for her parents? EXPLAIN.
AA, AO, BB, BO, AB---one parent donated an A and the other parent donated a B
How do MOST mutations affect an organism?
neutral
How could a gene mutation affect an organism?
It could alter ONE protein.
When does crossing over occur and what form of DNA is involved?
Meiosis 1- genes from homologous chromosomes are switched.
How could a chromosome mutation affect an organism?
It could alter MANY proteins due to affecting MANY genes.
Give an example of a genotype.
HH, Hh, hh, homozygous dominant, etc.
What is a phenotype?
The physical appearance of an organism due to the genotype inherited by an organism.
How many chromosomes would be found in the egg cell for this organism?
22
What is an inherited mutation?
A mutation passed on from parent to offspring.
What is an acquired mutation?
A mutation that a person obtains during their lifetime due to environmental factors.
What is a zygote?
A fertilized cell made from the combination of sperm and egg.
How many chromosomes do diploid human cells contain?
46
What is a trait?
A characteristic of an organism that is specified by an organism's genotype and expressed by an organism's phenotype.
Draw a punnett square for two heterozygous parents with purple phenotypes (dominant to white). Summarize the genotype and phenotype for both the parents and offspring.
Parent 1: Bb (purple), Parent 2: Bb (purple), 1/4 offspring: BB (purple), 2/4 offspring: Bb (purple), 1/4 offspring: bb (white)
What is genetic recombination? Give an example of a process that contributes to this.
Genetic recombination is the mixing of genetic information that can be passed from parent to offspring- Ex: Crossing over, independent assortment, segregation
homozygous
genotype with two of the same type of allele
Abby has type AB blood. What are the POSSIBLE genotypes for her parents? EXPLAIN.
AA, AO, BB, BO, AB---one parent donated an A and the other parent donated a B
Given an example for a phenotype.
Brown eyes, black hair, 5'6", etc.
dominant allele
allele that is stronger than another so that the trait of an organism will show the dominant phenotype when at least one dominant allele is present
How many nitrogen bases are found in ONE mRNA codon?
3
recessive allele
weaker allele that will only result in a recessive phenotype when two of these alleles are present in a genotype
How can you tell if a situation is demonstrating a codominant pattern for inheritance?
The heterozygote will have both parent phenotypes present.
probability
the likelihood that a certain event will occur
When does a chromosome mutation occur?
meiosis
How many chromosomes do human gametes have?
23
How do the cells produced in meiosis compare to parent (germ) cells?
They are different.