TEST 1 Flashcards
The purpose of meiosis is to
Produce haploid gametes
Body cells (not sex cells) are known as:
somatic cells
What happens during early metaphase of mitosis?
Chromosomes align at metaphase plate
The central point that connects the 2 rod-like potions of the chromosomes is know as:
centromere
At the end of meiosis, each of the 4 daughter cells, which will be involved in sexual reproduction will exist in a ______ state.
Haploid
Which of the following cellular components is responsible for executing the distribution of chromosomes during the process of mitosis?
Microtubules
Prior to mitosis, each chromosomes of a eukaryotic cell consists of a pair of identical structures called
sister chromatids
Two chromosomes in a nucleus that carry genes controlling the same inherited characteristics are
homologous chromosomes
What is the final product of mitosis
2 daughter cells identical to the parent cell
Which of the following is a phase that occurs during mitosis?
Prophase
NOT Meiosis, S phase, G2 phase, G1 phase
How many different combinations of maternal and paternal chromosomes can be packaged in gametes made by an organism with a diploid number of 8 (2n=8)?
16
Mendel proposed that each individual organism (pea plant) carried how many alleles, or copies of a gene?
2
2 plants are crossed, resulting in offspring with a 3:1 ratio for a particular trait. What does this suggest?
that the parents were both heterozygous for a single trait
According to Mendel’s model, bc of the ______ of chromosomes during meiosis, all possible combinations of gametes will be formed in equal frequency
independent assortment
In the cross AaBcCc x AaBbCc, what is the probability of producing the genotype AABBCC?
1/64
Which of the following calculations require that you utilize the addition rule (sum rule)?
Calculate the probability of a child having either sickle-cell anemia or cystic fibrosis if parents are each heterozygous for both.
Pedigree - disease allele is rare and therefore individuals marrying into the family are unlikely to have the defective allele.
Dominant - its in every generation
An organism inherits 2 diff alleles for a single trait, one from its mother and one from its father is known as
Heterozygote
The pedigree what is the genotype of individual 5?
aa
The principle of segregation states that:
In a heterozygote, 2 diff alleles separate from each other during the formation of gametes.
The definition of dominant allele is:
The expressed factor in the heterozygote
Which is an example of codominance?
in roan cattle, you can see a mix of both red and white furs
Mendel’s monohybrid results served as the basis for all but one of his postulates. Which postulate was not based on these results?
When 2 independent events occur simultaneously, the probability of the 2 outcomes occurring in combination is equal to the product of their individual probabilities of occurrence.
NOT
Genetic characters are controlled by unit factors existing in pairs in individual organisms.
When 2 unlike unit factors responsible for a single character are present in a single individual, one unit factor is dominant to the other, which is said to be recessive.
During the formation of gametes, the paired unit factor separate, or segregate, randomly so that each gamete receives one or the other with equal likelihood.
Which of the following best describes the relationship at the molecular level between mutant alleles and phenotype?
A mutant allele can have different effects depending on the gene product’s function.
Chi-square analysis can help us to decide whether
our observations of an event from our expectations
In tomatoes, red fruit color is dominant (Y) and yellow is recessive (y). A red fruited plant, when crossed with a yellow-fruited plant , produces offspring about half of which are yellow fruited and half of which are red fruited. What are the genotypes of the parents?
Yy and yy
Curly hair is caused by a dominant gene in humans. This trait is rare among norther Europeans. If a curly-haired northern European marries a person with straight hair, what proportions of their offspring would be expected to have curly hair, assuming the curly haired individuals was a heterozygote?
50%
In a mating between individuals with the genotypes IAi x ii what percentage of the offspring are expected to have the O blood type?
50%
The trait of medium sized leaves in iris is determined by the genetic condition PP’. Plants with large leaves are PP, whereas pants with small leaves are P’P’. A cross is made between 2 plants each with medium-sized leaves. What is the term for this allelic relationship?
incomplete dominance
Achondroplasia is a form of human dwarfism. If 2 individuals with achondroplasia have children with the following ratio, 2 dwarf to 1 wild type, what is the mems of inheritance of this phenotype?
Dominant lethal
A mutation is a gene often results in a reduction of the produce of that gene. The term for this type of mutation is
loss of function mutation
The Hydrangea plants in the Tyler neighborhoods usually have blue petals bc of the acidity of the sandy soils. If you wanted to have hydrangeas with pink petals, you read that you need to add garden lime fertilizer to the soil to raise the ph value into the alkaline range. You would conclude that petal color in these plants…
is determined by the environment
In cats, there is a gene which causes additional toes in its mutant form. Cats which have this gene variant always have additional toes, but the number of additional toes varies. This is an example of
expressivity.
