Chapter 11 Study Guide Flashcards
An allele is
Different forms of a gene
If a homozygous tall and homozygous short are crossed what happens?
The recessive trait disappears.
What is a Punnett Square used for?
To determine the actual outcome of a cross of genes.
Homozygous
Organisms that have two identical alleles for a particular trait.
Heterozygous
Organisms that have different alleles for a particular trait.
Phenotype
The physical characteristics of an organism
Genotype
Aa, AA, aa
Codominance
A situation in which a gene has more than two alleles.
What does meiosis result in the formation of?
Four haploid gamete cells
What does mitosis result in the formation of?
Two genetically identical daughter cells
What happens when gametes are produced by meiosis?
The chromosome number of an organism is maintained.
The relative locations of genes on a chromosome are shown on what?
Gene Map
During meiosis, what halves?
The chromosome number
What happens during Telophase 1?
The chromosome number is reduced.
What is incomplete dominance?
When neither trait is truly dominant over the other. When a redhead and a brunette have blonde children, that is complete dominance.
What is used to construct a gene map?
Recombination rate
What happens during meiosis 1?
Alles for the same trait are separated from each other.
In males, meiosis results in four equal-sized gametes called…?
Sperm
In females, only one large what results from meiosis?
Egg
What three cells are usually not included in reproduction?
Polar Bodies
Cells undergo a round of DNA replication, forming duplicate chromosomes in what phase…?
Interphase 1
What happens during Prophase 1?
Each chromosome pairs with its corresponding homozygous chromosome to form a tetrad.
Spindle fibers attach to the chromosomes in..?
Metaphase 1
The fibers pull the homologous chromosomes toward opposite ends of the cell in..?
Anaphase 1
What happens in Metaphase 2?
The chromosomes line up in a similar way to the metaphase stage of mitosis.
What happens in Anaphase 2?
The sister chromatids separate and move towards opposite ends of the cell.
During prophase 1 of meiosis, homologous chromosomes may cross over and exchange portions of their…?
Chromatids
Gamete
Reproductive cells (Sperm and Egg)
Diploid
2 copies of each gene
What is genetics the study of?
Inheritance: the DNA you get from your parents.
Gene
A stretch of DNA that controls a trait.
During gamete formation, alleles are segregated from each other so that each gamete carries only a…?
Single copy of each gene
Each F1 plant produces two types of gametes. These are the alleles for what and what?
Shortness and tallness.
True-Breeding
If something is allowed to self-pollinate they would produce offspring identical to themselves.
Hybrids
The offspring of crosses between parents with different traits.
Independent Assortment
Genes for different traits can segregate independently during the formation of gametes.
What is it called when there’s a gene with more than two alleles.
Multiple alleles
Polygenic Traits
Traits controlled by two or more genes.
As homologous chromosomes pair up and form tetrads in meiosis 1, they may exchange portions of their chromatids in a process called..?
Crossing-Over
