Biology Chapter 5 Test
In a dihybrid cross involving two autosomal traits on different chromosomes in which the parents are purebred for the opposite form of both traits, how many of the offspring would be expected to be homozygous for both traits?
1 out of 16
If a cell had 12 chromosomes at the beginning of meiosis II, how many would each daughter cell have after the completion of meiosis II?
12
Assuming complete dominance, what is the expected ratio of genotypes of the offspring following the cross of two heterozygotes?
1:2:1
How many chromosomes did you inherit from your father?
23
How many chromosomes and chromatids would a typical human cell have after duplication but before mitosis?
46 chromosomes, 92 sister chromatids
Human white blood cells are often multinucleated (in other words, have more than one nucleus). How many chromosomes would be present in a human white blood cell with two nuclei?
92
What is the chromosome abnormality that causes down syndrome?
A nondisjunction results in a person with an extra copy of chromosome 21
In the picture above, what is the singular blue part?
A sister chromatid
What is a carrier?
An individual that is healthy but carries one disease-causing recessive allele
When does the cell plate form during cell division?
At the completion of plant cell mitosis
The following F1 cross is made: BBGg x Bbgg. Which is not a possible outcome in the F2 generation?
BbGg
DNA plus its associated proteins is called a ________.
Chromatin
Which of the following is not apart of mitosis?
Cytokinesis
If it were to be stretched out, the DNA in one of your cells would be taller than you. How does such a large quantity of DNA fit within the nucleus of one of your cells?
DNA is associated with proteins that compact the DNA to form a package called chromatin
What do we call a genetic cross that follows two separate characters, such as pea seed color and pea seed shape?
Dihybrid Cross
A breeder wants to set up a program to produce zebrafish with long fins. Having long fins is a dominant trait compared to the short-finned wild type. Before she can market her zebrafish, she needs to perform a test cross on the long-finned fish she plans to use as a breeder. How can she tell whether her fish are homozygous or heterozygous for the long-finned trait?
Do several test crosses between the long-finned fish and the short-finned fish; if the offspring are always long finned, the long-finned parent is probably homozygous.
Imagine that the eye color in cats is controlled by a single gene and that there are two alleles: black eyes and orange eyes. All the offspring of a cross between black eyed cats and an orange-eyed cat have black eyes. This mean that the allele for black is__________ the allele for orange eyes.
Dominant to
Imagine that five hypothetical genes are arranged on a chromosome in the following order: G--H--I--J--K. Which two genes are most likely to have a crossover occur between them?
G and K
If mitosis makes somatic cells, what does meiosis make?
Gametes
What type of cells do not undergo mitosis?
Gametes
Gorillas have 48 chromosomes. How does the number of chromosomes in a gorilla sperm compare with that of a human sperm?
Gorilla sperm have one more chromosome than human sperm
What is Mendel's Law of Independent Assortment?
Independent assortment means that each pair of alleles segregates independently of the other pairs of alleles.
Which processes generate genetic variation during sexual reproduction?
Independent assortment, crossing over, and random fertilization
Cells spend most of their lives in...
Interphase
During which phase of the cell cycle are the chromosomes duplicated?
Interphase
In a human which of the following are present?
Klinefelter syndrome, where a male has 2 X and one Y chromosome
Since an XO female can survive, but an OY male cannot, what can we conclude about the genetic information in the X and Y chromosomes?
Males need at least one X chromosome to survive
What produces genetically unique daughter cell?
Meiosis
When does crossing over occur?
Meiosis I
Which process requires DNA to undergo duplication before it can proceed?
Meiosis and Mitosis
Chromosomes are often represented as an X, with two sister chromatids attached at the centromere. Do chromosomes always look like an X?
No, chromosomes only look like an X following DNA replication, and before cell division; the rest of the time, they only have one sister chromatid e
Is the number of chromosomes in each cell of an organism a good indicator of the complexity of that organism?
No, the number of chromosomes does not indicate how complex an organism is.
Which of the following is the correct sequence of events during mitosis?
Nuclear membrane dissolves, chromosomes line up, sister chromatids split, nuclear membrane forms
What process involving cell division results in daughter cells that are NOT identical to the parent cell?
Sexual reproduction
As mitosis begins, __________ are linked together at the centromere.
Sister chromotids
What specifically separates during anaphase of mitosis?
Sister chromotids
The inheritance pattern for red-green color blindness is different for males compared to females. Red-green color blindness is much more common in males than in females. What does this suggest about the gene for red-green color blindness?
The gene for this trait is located on the X sex chromosome
The recessive trait is expressed in an individual when
The individual has two recessive alleles
What is the difference between two alleles of the same gene?
The information they carry. For example, one allele might carry the information for blue eye pigment, while the other carries the information for brown eye pigment.
Define Mendel's law of independent assortment.
The inheritance of one character has no effect on the inheritance of another character.
What is cytokinesis?
The stage of the cell cycle after the cell has divided its DNA and during which the cytoplasm gets divided
Females have what type of chromosomes?
XX
Cell theory states that ________.
all life is made up of cells, and cells arise from preexisting cells
When are the chromosomes of a cell duplicated?
before a cell divides
An individual can be homozygous for a trait, which means_______
both of their alleles carry the same information
How does cytokinesis occur in a dividing animal cell?
by the formation of a cleavage furrow
Genes are located on ________.
chromosomes
Somatic cells are...
diploid (2n)
A testcross is preformed to determine if a specific individual is a carrier. The results generate a 50/50 ratio of phenotypes. The test subject is therefore_________
heterozygous
A testcross is preformed to determine if a specific individual is a carrier. The results generate a 50/50 ratio of phenotypes. The test subject is therefore_________.
heterozygous
What specifically separates during meiosis I?
homologous chromosomes
The offspring produced via asexual reproduction are genetically ________ to the parents.
identical
if a women with curly hair and a man with straight hair have a child with wavy hair, the gene for this characteristic of hair shows....
incomplete dominance
When I say a flower is "purple," what have I described?
its phenotype
Genes located near one another on the same chromosome are often inherited together. These are called ________.
linked genes
Recessive disorders related to genes found on the X chromosome but not on the Y chromosome are more commonly expressed in ________.
males
What produces four daughter cells?
meiosis
Assuming incomplete dominance, if a homozygous red-flowered plant is crossed with a homozygous white-flowered plant, what will be the color of the offspring?
pink
What specifically separates during meiosis II?
sister chromatids
What happens during cytokinesis?
the cytoplasm is split and distributed to the two daughter cells created during mitosis
What is crossing over?
the exchange of pieces of homologous chromosomes
A homozygous milk chocolate Easter bunny is crossed with a homozygous dark chocolate Easter bunny. Assuming dark chocolate is dominant over milk chocolate and the traits segregate according to Mendelian genetics, which traits will be observable in the offspring?
they will all be dark
When one cell goes through cell division, it produces ________.
two identical cells
Like mitosis, meiosis involves duplication of the chromosomes before division starts. However, there are __________ rounds of cell division during meiosis and __________ during mitosis.
two; one
If genes are described as "sex linked," then they are ________.
typically on the X chromosome
Upon fertilization, the egg and sperm fuse to form a single cell called a(n) ________
zygote
