Unit 1 test Flashcards
During which stage of meiosis does synapsis occur?
prophase I
If frog sperm contains 13 chromosomes, how many chromosomes would the skin cell of a frog contain?
26
If you are a human with XX chromosomes in your somatic cell, what will be your biological sex?
female
Is this statement true or false?
“Only sperm and eggs contain sex chromosomes and somatic cells do not contain sex chromosomes.”
false
Is anaphase of mitosis more similar to anaphase 1 or anaphase 2 of meiosis?
Anaphase II- the sister chromatids are being pulled apart and segregated
If a parent cell contains 4 homologous pairs of chromosomes, how many Individual chromosomes will the gamete have?
4
In anaphase 2, one of the large chromosome’s sister chromatids fails to separate at the centromere.
If meiosis leads to the formation of sperm, how many chromosomes will each sperm have?
2 of the sperm will have 2 chromosomes, 1 of the sperm will have 1 chromosme, and 1 sperm will have 3 chromosomes
What is the term for the number of chromosomes contained in a gamete?
haploid
What is the number of chromosomes in a human somatic cell?
46
If a parent cell starts of with two pairs of homologous chromosomes, name the stage of meiosis this represents (separate and move towards opposite poles)
anaphase I
Crossing over in prophase 1 causes the recombination of DNA which leads to more genetic diversity in gametes.
Describe one event in meiosis in which also results in the increased genetic diversity of gametes.
the independent assortment of maternal and paternal chromosomes results in more genetic diversity in the gametes
What is the term for a fertilized egg?
zygote
If a parent cell starts off with two pairs of homologous chromosomes, name the stage of meiosis this represents?
(formation of spindle apparatus, and chromosomes align in the middle)
metaphase II
What are the sex chromosomes found in people who are born biological female?
xx
What is another term for eggs and sperm?
gametes
What term is used to describe DNA that is composed of a mixture of two or more different sources of DNA?
For example, a chromosome that contains both maternal and paternal DNA
recombinant DNA
What is the main difference between anaphase 1 and anaphase 2 of meiosis?
Anaphase II has sister chromatids being pulled toward opposite poles and anaphae I has each side of a homologous pair being pulled toward opposite poles
What is the term for number of chromosomes found in a somatic cell?
diploid
What is the number of chromosomes found in a human gamete
23
If a parent cell starts off with two pairs of homologous chromosomes, name the stage of meiosis
(sister chromatids of each chromosome separate and move towards opposite poles, where they become unreplicated chromosomes)
anaphase II
The term for the pairing up of two homologous chromosomes at the beginning of meiosis.
synapsis
What do you call chromosomes that do not code for biological sex?
autosomes
At the end of spermatogenesis, how many sperm cells are produced?
4
If a somatic cell of a kangaroo contains 16 chromosomes, how many chromosomes would a kangaroo egg contain?
8
If a parent cell starts off with two pairs of homologous chromosomes, name the stage represented.
(nuclear envelope break downs, spindle apparatus forms and chromosomes duplication occurs)
prophase II
During which stage of meiosis does crossing over occur?
prophase I
In meiosis 1, what do you call the random segregation of the members of a homologous pair to opposite poles?
indeppendent assorment
What is the main difference between anaphase of mitosis and anaphase 2 of meiosis?
mitosis is identical sister chromatids beong pulled toward opposite poles and meiosis is sister chromatids being pulled to opposite poles but they arent identical. This is because they went through crossing over
What do you call chromosomes that are the same size and which have the same genes that code for the same traits contained at the same loci?
homologous chromosomes
During which stage does members of homologous pairs separate to opposite poles?
anaphase I
If a parent cell starts of with two pairs of homologous chromosomes, name the stage of meiosis represented.
(chromosomes reach opposite poles, cytokinesis occurs)
telophase II
Why does meiosis need to result in the production of haploid gametes?
This happens so when the sperm and egg fertalize, the diploid # is restored in the resulting zygote
What do you call the places on a chromosome where genes are located?
loci (plural)
If a parent cell starts of with two pairs of homologous chromosomes, name the stage of meiosis represented.
(alignment of paired chromosomes along the center of a cell, ensuring that two complete copies of chromosomes are present in the resulting in two daughter cells)
metaphase I
This is the collective term used to describe both oogenesis and spermatogenesis
gametogenesis
What is the number of functioning eggs produced after oogenesis?
1
What is the name for the exchange of genetic material between maternal and paternal homologous chromosomes?
crossing over
What is the main difference between metaphase 1 and metaphase 2?
Metaphase I is when homologous pairs line up in the middle on the equatorial plate and metaphase II is when 1 side of each homologous pair lines up in the middle
During which stage of meiosis do sister chromatids separate to opposite poles?
anaphase II
Chromosomes that come form your mother are called _____ chromosomes
maternal
If a parent cell starts of with two pairs of homologous chromosomes, name the stage of meiosis represented.
(crossing over and recombination of genetic material)
prophase I
If you are human with XY chromosomes in your somatic cells, what will be your biological sex?
male
What do microtubules attach themselves to on a chromosome?
centromere
Would gametes produced be identical if crossing over failed to happen during prophase 1 of meiosis
No, they would still have independent assortment to create genetic diversity
If a parent cell starts of with two pairs of homologous chromosomes, name the stage of meiosis represented.
(A cleavage furrow appears, and by the end of this stage the parent cell has divided into two daughter cells, dividing of cytoplasm occurs)
telophase I
Chromosomes that come from your father are called ______ chromosomes
paternal
What are the sex chromosomes in people who are for biological males?
xy
Assume that anaphase 1 improper segregation occurs and both members of the large homologous pair end up in the same pole instead of in opposite poles.
If anaphase 2 occurs properly after this, how many chromosomes will each sperm have?
2 of the sperm will have 1 chromosome each and the other 2 sperm will have 3 chromosomes each
For meiosis, what is the most important difference between interphase and interkinesis?
interphase is when DNA replication occurs and DNA replication does not occur in interkinesis
if this image was labeld metaphase II, what would be wrong with this label and why
in Metaphase II all the chromosomes should be lined up in the middle, but in this image, the pairs are lined up which would mean the photo is of metaphase I not II
Is it possible for the creation of healthy normal offspring if the sperm and egg do not contain the same number of chromosomes?
No, the diploid # cant be restored and there would be chromosomes missing their pairs
What is the name for the protein fibers that attach to the centromeres of chromosomes?
microtubles or spindle fibers
What is a tetrad?
a structure formed from 4 sister chromatids
Mitosis and Meiosis are different processes, but for both to occur, something needs to happen during interphase.
what needs to happen?
DNA replication
The mosquito Aedes aegypti, has 6 chromosomes in its somatic cell. How many chromosomes would be found in one sperm cell?
3
What is a termed to describe a structure formed from 4 sister homologous chromatids
tetrad
trisomy 21 results in this condition
down syndrome
What condition is characterized by infertility and delayed or missing secondary sexual characteristics, like breast development and menstrual cycle. This condition is also often characterized by short stature, wide necks and puffy hands and feet
turner syndrome
a human whose sex chromosomes are XXY has what type of condition
klinefelter syndrome
what is nondisjunction
the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division in meiosis
define trisomy
the condition of having and extra chromomsome creating a third homologous chromosome when there should only be a homologous pair (2 homologous chromosomes)
a human who only has one sex chromosomel which is an x chromosome, will have what type of condition
turner syndrome
what is the biological sex of a person with Klinefelter Sydrome
male
How are the chromosomes of someone with down syndrome different than someone without it
they have a 3rd copy of chromosome 21 some without only has 2 copies of chromosome 21
define monosomy
when 1 chromosome of a homologous pair is missing
what is the biological sex of a person with Turner syndrome
female
the condition of having three members of a type of chromosome instead of the typical homologous pair
trisomy
what sex chromosomes are found in a person with Klinefelter syndrome
xxy
The condition of having one chromosome without its homologous partner
monosomy
what sex chromosomes are found in a person with turner syndrome
x
