BIOL 101 QUESTIONS AND ANSWERS EXAM LATEST
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Mitosis is a cellular process that produces
A. Two genetically identical daughter cells
B. Four genetically identical daughter cells
C. Two similar, but not genetically identical daughter cells
D. Four similar, but not genetically identical daughter cells
A. Two genetically identical daughter cells
How many chromosomes do human somatic (body) cells have?
A. 23
B. 45
C. 46 (23 pairs)
D. 47
C. 46 (23 pairs)
What is a gene?
A. A malignant growth resulting from uncontrolled cell division
B. A segment of DNA that controls the production of a protein
C. An arrangement of chromosomes used to detect genetic abnormalities
B. A segment of DNA that controls the production of a protein
How many chromosomes would a typical human cell have after mitosis but
before cytokinesis?
A. 0
B. 23
C. 46 (46 per cell but the cell has not yet divided)
D. 92
D. 92
Meiosis
The form of cell division by which sex cells produce gametes, with half the number of
chromosomes, are produced.
Gametes
sperm or egg cells
At the start of Meiosis vs. At the end of Meiosis
Start: there are 46 chromosomes (23 pairs) in the parent cell
End: there are 23 chromosomes in each of four new cells that were produced
Two cell divisions in Meiosis
Meiosis I and Meiosis II
Where does Meiosis occur?
Occurs only in gonads -(testes [sperm] or ovaries [eggs]).
**Meiosis in males is called spermatogenesis and produces sperm
**Meiosis in females is called oogenesis and produces eggs (ovum)
Sexual Reproduction
Creates a diploid zygote from the fertilization of the haploid egg and haploid sperm.
, Diploid
46 chromosomes (23 pairs)
**Haploid = 23 chromosomes
**Haploid (sperm) + Haploid (egg) = Diploid (zygote)
Types of Chromosomes
Autosomal & Sex
Autosomal
all chromosomes in a person's cells except for those that determine the sex. 22 pairs
Sex
chromosomes that determine sex. 1 pair
**XX: female, XY: male
The Process of Gamete Formation
-Interphase I
-Meiosis I (4 Phases)
*Prophase I
*Metaphase I
*Anaphase I
*Telophase I
-Meiosis II (4 phases)
*Prophase II
*Metaphase II
*Anaphase II
*Telophase II
Interphase I
Similar to mitosis interphase.
**Chromosomes (coiled up DNA & proteins) replicate
**Each duplicated chromosome consists of two identical sister chromatids attached at
their centromeres
Meiosis I
Cell division that reduces the chromosome number by one-half.
--Four phases: Prophase I, Metaphase I, Anaphase I, Telophase I
**46 chromosomes -> 23 chromosomes
Prophase I
o Chromosomes condense.
o Synapsis (coming together) occurs - Homologous chromosomes (chromosome pairs)
come together to form a tetrad.
o Tetrad is two chromosomes or four chromatids (sister and non-sister chromatids).
Non-Sister Chromatids
¥ Homologous chromosomes contain DNA that codes for the same genes, but different
versions of those genes
¥ Genes occur at the same loci (location on a chromosomes)
**gene (& gene variation)- blood type (both chromosomes would have the gene, but the
"versions" would be the types of blood that you actually have)
Homologous Chromosomes
UPDATE.Buy Quality Materials!
Mitosis is a cellular process that produces
A. Two genetically identical daughter cells
B. Four genetically identical daughter cells
C. Two similar, but not genetically identical daughter cells
D. Four similar, but not genetically identical daughter cells
A. Two genetically identical daughter cells
How many chromosomes do human somatic (body) cells have?
A. 23
B. 45
C. 46 (23 pairs)
D. 47
C. 46 (23 pairs)
What is a gene?
A. A malignant growth resulting from uncontrolled cell division
B. A segment of DNA that controls the production of a protein
C. An arrangement of chromosomes used to detect genetic abnormalities
B. A segment of DNA that controls the production of a protein
How many chromosomes would a typical human cell have after mitosis but
before cytokinesis?
A. 0
B. 23
C. 46 (46 per cell but the cell has not yet divided)
D. 92
D. 92
Meiosis
The form of cell division by which sex cells produce gametes, with half the number of
chromosomes, are produced.
Gametes
sperm or egg cells
At the start of Meiosis vs. At the end of Meiosis
Start: there are 46 chromosomes (23 pairs) in the parent cell
End: there are 23 chromosomes in each of four new cells that were produced
Two cell divisions in Meiosis
Meiosis I and Meiosis II
Where does Meiosis occur?
Occurs only in gonads -(testes [sperm] or ovaries [eggs]).
**Meiosis in males is called spermatogenesis and produces sperm
**Meiosis in females is called oogenesis and produces eggs (ovum)
Sexual Reproduction
Creates a diploid zygote from the fertilization of the haploid egg and haploid sperm.
, Diploid
46 chromosomes (23 pairs)
**Haploid = 23 chromosomes
**Haploid (sperm) + Haploid (egg) = Diploid (zygote)
Types of Chromosomes
Autosomal & Sex
Autosomal
all chromosomes in a person's cells except for those that determine the sex. 22 pairs
Sex
chromosomes that determine sex. 1 pair
**XX: female, XY: male
The Process of Gamete Formation
-Interphase I
-Meiosis I (4 Phases)
*Prophase I
*Metaphase I
*Anaphase I
*Telophase I
-Meiosis II (4 phases)
*Prophase II
*Metaphase II
*Anaphase II
*Telophase II
Interphase I
Similar to mitosis interphase.
**Chromosomes (coiled up DNA & proteins) replicate
**Each duplicated chromosome consists of two identical sister chromatids attached at
their centromeres
Meiosis I
Cell division that reduces the chromosome number by one-half.
--Four phases: Prophase I, Metaphase I, Anaphase I, Telophase I
**46 chromosomes -> 23 chromosomes
Prophase I
o Chromosomes condense.
o Synapsis (coming together) occurs - Homologous chromosomes (chromosome pairs)
come together to form a tetrad.
o Tetrad is two chromosomes or four chromatids (sister and non-sister chromatids).
Non-Sister Chromatids
¥ Homologous chromosomes contain DNA that codes for the same genes, but different
versions of those genes
¥ Genes occur at the same loci (location on a chromosomes)
**gene (& gene variation)- blood type (both chromosomes would have the gene, but the
"versions" would be the types of blood that you actually have)
Homologous Chromosomes
