6. INTERPHASE MITOSIS
LATE INTERPHASE
nuclear
envelope chromatin
nucleolus
centriole
pairs
LATE PROPHASE METAPHASE
beginning of
spindle formation
kinetochore
pole
polecondensing
chromosomes
spindle
microtubules
Duplicated chromosomes in
relaxed state; duplicated
centrioles remain clustered.
Chromosomes condense
and shorten; spindle
microtubules begin to form
between separating
centriole pairs.
Nucleolus disappears;
nuclear envelope breaks
down; spindle microtubules
attach to the kinetochore
of each sister chromatid.
Kinetochores interact;
spindle microtubules line up
chromosomes at cell's
equator.
EARLY PROPHASE
7. INTERPHASE
ANAPHASE
"free" spindle
fibers
chromosomes
extending nuclear envelope
re-forming
Sister chromatids separate
and move to opposite poles
of the cell; spindle
microtubules push poles
apart.
One set of chromosomes
reaches each pole and relaxes
into extended state; nuclear
envelopes start to form
around each set; spindle
microtubules begin to
disappear.
Cell divides in two; each
daughter cell receives one
nucleus and about half of
the cytoplasm.
Spindles disappear, intact
nuclear envelopes form,
chromosomes extend
completely, and the
nucleolus reappears.
TELOPHASE INTERPHASE OF
DAUGHTER CELLS
CYTOKINESIS
17. MEIOSIS I
Prophase I. Duplicated chromosomes condense.
Homologous chromosomes
pair up and chiasmata occur as chromatids of
homologues exchange parts. The nuclear envelope
disintegrates, and spindle microtubules form.
paired homologous
chromosomes
spindle
microtubule
chiasma
18. MEIOSIS I
Metaphase I. Paired homologous
chromosomes line up along the
equator of the cell. One homologue of
each pair faces each pole of the cell
and attaches to spindle microtubules
via its kinetochore (blue).
recombined
chromosomes
21. MEIOSIS II
Prophase II.
If chromosomes
have relaxed after
telophase I, they
recondense. Spindle
microtubules re-form
and attach to the
sister chromatids.
Metaphase II.
Chromosomes line
up along the equator,
with sister chromatids
of each chromosome
attached to spindle
microtubules that lead
to opposite poles.
Anaphase II.
Chromatids separate
into independent
daughter chromosomes,
one former chromatid
moving toward each
pole.
Telophase II.
Chromosomes finish
moving to opposite
poles. Nuclear
envelopes re-form,
and the chromosomes
become extended
again (not shown here).
Four haploid
cells.
Cytokinesis results in
four haploid cells,
each containing one
member of each pair
of homologous
chromosomes (shown
here in condensed
state).
Figure: 11-1
Title:
Cell division in eukaryotes enables asexual reproduction
Caption:
(a) In unicellular microorganisms, such as the protist Paramecium, cell division produces two new, independent organisms. (b) Yeast, a unicellular fungus, reproduces by cell division. (c) Hydra, a freshwater relative of the sea anemone, grows a miniature replica of itself (a bud) on its side. When fully developed, the bud breaks off and assumes independent life. (d) Trees in an aspen grove are often genetically identical. Each tree grows up from the roots of a single ancestral tree. This photo shows three separate groves near Aspen, Colorado. In fall, the appearance of their leaves shows the genetic identity within a grove and the genetic difference between groves.
Figure: 11-4
Title:
Mitotic and meiotic cell division in the human life cycle
Caption:
Within ovaries, meiotic cell division produces eggs; within testes, meiotic cell division produces sperm. Fusion of egg and sperm produce a fertilized egg that develops into an adult by numerous mitotic cell divisions and differentiation of the resulting cells.
Figure: 11-6
Title:
Human chromosomes during mitosis
Caption:
The DNA and associated proteins in these duplicated human chromosomes have coiled up into the thick, short sister chromatids attached at the centromere. Each visible strand of “texture” is a loop of DNA. During cell division, the condensed chromosomes are about 5 to 20 micrometers long. At other times, the chromosomes uncoil until they are about 10,000 to 40,000 micrometers long.
Figure: 11-7
Title:
The karyotype of a human male
Caption:
Staining and photographing the entire set of duplicated chromosomes within a single cell produces a karyotype. Pictures of the individual chromosomes are cut out and arranged in descending order of size. The chromosome pairs (homologues) are similar in both size and staining pattern and have similar genetic material. Chromosomes 1 through 22 are the autosomes; the X and Y chromosomes are the sex chromosomes. Notice that the Y chromosome is much smaller than the X chromosome. If this were a female karyotype, it would have two X chromosomes.
Figure: 11-8 left
Title:
Mitotic cell division in an animal cell left
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 right
Title:
Mitotic cell division in an animal cell right
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 left part a
Title:
Mitotic cell division in an animal cell left part a LATE INTERPHASE
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 left part b
Title:
Mitotic cell division in an animal cell left part b EARLY PROPHASE
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 left part c
Title:
Mitotic cell division in an animal cell left part c LATE PROPHASE
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 left part d
Title:
Mitotic cell division in an animal cell left part d METAPHASE
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 right part e
Title:
Mitotic cell division in an animal cell right part e ANAPHASE
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 right part f
Title:
Mitotic cell division in an animal cell right part f TELOPHASE
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 right part g
Title:
Mitotic cell division in an animal cell right part g CYTOKINESIS
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-8 right part h
Title:
Mitotic cell division in an animal cell right part h INTERPHASE OF DAUGHTER CELLS
Caption:
Question What would the consequences be if one set of sister chromatids failed to separate at anaphase?
Figure: 11-11 left
Title:
Meiotic cell division in an animal cell left
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 left part a
Title:
Meiotic cell division in an animal cell left part a Prophase I
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 left part b
Title:
Meiotic cell division in an animal cell left part b Metaphase I
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 left part c
Title:
Meiotic cell division in an animal cell left part c Anaphase I
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 left part d
Title:
Meiotic cell division in an animal cell left part d Telophase I
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 right
Title:
Meiotic cell division in an animal cell right
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 right part e
Title:
Meiotic cell division in an animal cell right part e Prophase II
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 right part f
Title:
Meiotic cell division in an animal cell right part f Metaphase II
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 right part g
Title:
Meiotic cell division in an animal cell right part g Anaphase II
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 right part h
Title:
Meiotic cell division in an animal cell right part h Telophase II
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
Figure: 11-11 right part i
Title:
Meiotic cell division in an animal cell right part i Four haploid cells
Caption:
In meiotic cell division (meiosis and cytokinesis), the homologous chromosomes of a diploid cell are separated, producing four haploid daughter cells. Each daughter cell contains one member of each pair of parental homologous chromosomes. In these diagrams, two pairs of homologous chromosomes are shown, large and small. The yellow chromosomes are from one parent (for example, the father), and the violet chromosomes are from the other parent (for example, the mother). Question What would the consequences be (for the resulting gametes) if one pair of homologues failed to separate at anaphase I? What if meiosis I was normal, but a pair of sister chromatids failed to separate at anaphase II?
