AP Biology Chapter 13
What does the term "somatic cell" mean?
A somatic cell is a cell that is not involved in sexual reproduction.
What does the term "life cycle" mean?
A life cycle involves the various stages of cellular development in organisms (humans, plants, etc.).
What does the term "zygote" mean?
A zygote is a diploid cell produced from fertilization.
Describe the three different types of life cycles.
The three types of life cycles include: 1. Human-creates diploid multicellular organism 2. Plant (Algae)-creates diploid multicellular organism (sporophyte) from a haploid multicellular organism (gametophyte) 3. Bacteria (Fungi)-creates a haploid unicellular or multicellular organism
What exactly is meant by the alteration of generations?
This means a life cycle that includes both diploid and haploid stages that are multicellular.
What does the term "diploid cell" mean?
A diploid cell is a cell that is 2n, or a cell that has 2 copies of each chromosome.
What does the term "haploid cell" mean?
A haploid cell is a cell that is n, or a cell that has only 1 copy of each chromosome.
What does the term "karyotype" mean?
A karyotype is a diagram that arranges chromosomes into homologous pairs based upon size and shape.
Of the following human trisomies, the one that generally has the most severe impact on the health of the individual is... A) Trisomy 21 B) Klinefelter syndrome (XXY) C) Trisomy X D) XYY E) All of the above have equal impact
A) Trisomy 21 (Down's syndrome)
Compare and contrast asexual and sexual reproduction.
Asexual and sexual reproduction differ in their execution but are similar in purpose/utility. Specifically, asexual reproduction involves one organism creating/morphing into a new organism requiring one parent only, and as a result decreasing genetic diversity within the population. However, sexual reproduction involves two organisms exchanging DNA to form a genetically unique orgasnism, thus increasing the amount of genetic diversity within the population.
Describe genetic variation involving separation of homologs.
At anaphase I, duplicated chromosomes of each homologous pair move more toward opposite poles, but sister chromatids remain attached.
What does the term "autosomes" mean?
Autosomes are the non-sex chromosomes of an organism. These include the other 22 chromosome pairs (out of 23 total pairs) in humans.
Which of the following statements is true in regards to the statement: "Homologous chromosomes synapse and crossing over occurs"? A) The statement is true for mitosis only B) The statement is true for meiosis i only C) The statement is true for meiosis ii only D) The statement is true for mitosis and meiosis i E) The statement is true for mitosis and meiosis ii
B) The statement "Homologous chromosomes synapse and crossing over occurs" is true for meiosis i only
Which of the following terms belongs with the words synapsis, tetrads, and chiasmata? A) haploid B) crossing over C) autosomes D) prophase ii E) fertilization
B) crossing over
After telophase i of meiosis, the chromosomal makeup of each daughter cell is.. A) diploid, and the chromosomes are composed of a single chromatid B) diploid, and the chromosomes are composed of two chromatids C) haploid, and the chromosomes are composed of a single chromatid D) haploid, and the chromosomes are composed of two chromatids E) tetraploid, and the chromosomes are composed of two chromatids
B) diploid, and the chromosomes are composed of two chromatids
If nondisjunction occurs in meiosis ii during gametogenesis, what will be the result at the completion of meiosis? A) All the gametes will be diploid B) Two gametes will be n+1, and two will be n-1 C) One gamete will be n+1, one will be n-1, and two will be n. D) There will be three extra gametes E) Two of the four gametes will be haploid and the other two will be diploid
C) One gamete will be n+1, one will be n-1, and two will be n.
Which of the following is true of a species that has a chromosome number of 2n=16? A) The species is diploid with 32 chromosomes B) The species has 16 sets of chromosomes C) There are 8 homologous pairs D) During the S phase of the cell cycle there will be 32 separate chromosomes E) A gamete from this species has 4 chromosomes
C) There are 8 homologous pairs
Which of the following is true of the process of meiosis? A) two diploid cells result B) four diploid cells result C) four haploid cells result D) four autosomes result E) four chiasmata result
C) four haploid cells result
Which of the following is a term for a human cell that contains 22 pairs of autosomes and two X chromosomes? A) an unfertilized egg cell B) a sperm cell C) a male somatic cell D) a female somatic cell E) both A and D
D) a female somatic cell
Describe genetic variation involving synapsis and crossing over.
During prophase I, duplicate homologs pair up and formation of synaptonemal complex between them holds them to prepare for synapsis (pairing of chromosomes) as alleles on chromosomes cross over or switch chromosomes depending on their proximity to their matching allele along the chromosome.
Which of the following statements is true in regards to the statement: "Centromeres uncouple and chromatids are separated from each other"? A) The statement is true for mitosis only B) The statement is true for meiosis i only C) The statement is true for meiosis ii only D) The statement is true for mitosis and meiosis i E) The statement is true for mitosis and meiosis ii
E) The statement "Centromeres uncouple and chromatids are separated from each other" is true for mitosis and meiosis ii only
What is a karyotype? A) the set of unique physical characteristics that define an individual B) the collection of all the mutations present within a gene C) a unique combination of chromosomes found in a gamete D) a system of classfying cell nuclei E) a display of every pair of homologous chromosomes within a cell, organized according to size and shape
E) a display of every pair of homologous chromosomes within a cell, organized according to size and shape
Asexual reproduction and sexual reproduction are different in that... A) individuals reproducing asexually transmit 100% of their genes to their progeny, whereas individuals reproducing sexually only transmit 50% B) asexual reproduction produces offspring that are genetically identical to their parents, whereas sexual reproduction gives rise to genetically distinct offspring C) asexual reproduction involves a single parent, whereas sexual reproduction involves two D) asexual reproduction only requires meiosis, whereas sexual reproduction always involves meiosis E) all of the above
E) all of the above
What does the term "fertilization" mean?
Fertilization is the process involving the union of sperm (male gamete) and ovum (female gamete).
What does the term "homologous chromosomes" mean?
Homologous chromosomes are chromosomes that have the same DNA but contain different variations (alleles) of the same gene.
Describe genetic variation involving homologous pairs at the metaphase plate.
In metaphase I, chromosomes are positioned at metaphase plate as pairs of homologs that are products of crossing over instead of individual chromosomes.
How are karyotypes prepared?
Karyotypes are prepared by pairing chromosomes and ordering them by size and shape.
What is the difference between what occurs in Meiosis 1 and Meiosis 2?
Meiosis I involves the separation of homologous chromosomes with a product of diploid cells, while Meiosis II involves the separation of sister chromatids with a product of haploid cells.
What are the two broad goals of meiosis?
Meiosis has two primary goals: 1. Replication of DNA 2. Diversification of DNA
What does the term "meiosis" mean?
Meiosis is the cell process of reproduction that increases genetic diversity.
Summarize the comparison of mitosis and meiosis.
Mitosis involves making copies of chromosomes and changes cells from n>2n or haploid>diploid without exchange of DNA and genetic variation while Meiosis involves reproduction and creates genetically unique daughter cells from parent cells, transforming cells from 2n>n or diploid>haploid where Meiosis I includes the separation of homologous chromosomes and Meiosis II includes the separation of sister chromatids
What are the stages of Meiosis?
Remember "IPMAT x2" or: Interphase 1- Prophase 1 Metaphase 1 Anaphase 1 Telophase/Cytokinesis 1 Interphase 2 Prophase 2 Metaphase 2 Anaphase 2 Telophase/Cytokinesis 2
What does the term "sex chromosomes" mean?
Sex chromosomes are the X and Y chromosomes that determine the biological sex of an individual.