CELL REPRODUCTION- CHAPTER 8
CELL REPRODUCTION VOCABULARY- CHAPTER 8
(33 words)
1. Chromosome
2. histone
4. Centromere
5. chromatin
7. Sex chromosome
8. homologous chromosome
10. Diploid
11. haploid
13. Binary fission
14. asexual reproduction
16. Gamete
17. interphase
19. Prophase
20. spindle fibers
22. Anaphase
23. telophase
25. Synapsis
26. tetrad
28. Genetic recombination
30. Independent assortment
32. Polar body
33. sexual reproduction
3. chromatid
6. autosome
9. karyotype
12. mitosis
15. meiosis
18. cytokinesis
21. metaphase
24. cell plate
27. crossing-over
29. spermatogenesis
31. oogenesis
CHROMOSOMES

TIGHTLY PACKED DNA & HISTONE
PROTEINS COMPRISE
CHROMOSOMES.
HISTONES: PROTEINS THAT DNA
WRAPS AROUND TO FORM
CHROMOSOMES.
 NONHISTONE PROTEINS CONTROL
THE ACTIVITY OF DNA.

CHROMOSOMES ARE
MADE UP OF TWO
CHROMATIDS.
 CHROMATIDS ARE
IDENTICAL COPIES OF
DNA AND PROTEINS.
 CENTROMERE: THE
ATTACHMENT POINT FOR
TWO CHROMATIDS IN A
CHROMOSOME.


CHROMATIN: LOOSLEY PACKED DNA
& PROTEINS.
CHROMOSOME NUMBERS
EACH SPECIES HAS
A CHARACTERISTIC
CHROMOSOME
NUMBER.
 HUMANS: 46
 LETTUCE: 18

SEX CHROMOSOMES
THESE DETERMINE THE SEX OF THE
ANIMAL.
 HUMANS: MALES ARE XY, FEMALES
ARE XX.
 SOME OTHER TRAITS BESIDES SEX
ARE CARRIED ON THESE
CHROMOSOMES. AN EXAMPLE
WOULD BE TO MAKE BLOOD
CLOTTING PROTEINS.

AUTOSOMES

THESE ARE THE OTHER 44
CHROMOSOMES THAT DO NOT
DETERMINE ONE’S SEX.
HOMOLOGOUS
CHROMOSOMES
THESE ARE CHROMOSOMES THAT
HAVE THE SAME SIZE AND GENE
ARRANGEMENT.
 IN SEXUALLY REPRODUCING
ORGANISMS EACH PARENT GIVES
ONE HOMOLOGOUS CHROMOSOME
TO ITS OFFSPRING. THUS THE
OFFSPRING HAS TWO COPIES OF
EACH AUTOSOME.

KARYOTYPE
THIS IS A PHOTOMICROGRAPH OF
CHROMOSOMES.
 THE CHROMOSOMES ARE ARRANGED BY
SIZE FOR THE AUTOSOMES.
 THE SEX CHROMOSOMES ARE PUT NEAR
THE END OF THE PICTURE.

DIPLOID & HAPLOID CELLS
DIPLOID CELLS (2N): THESE HAVE
TWO COPIES OF HOMOLOGOUS
CHROMOSOMES AND HAVE TWO SEX
CHROMOSOMES.
 HAPLOID CELLS (1N): THESE HAVE
ONLY ONE COPY OF AUTOSOMES
AND HAVE ONE SEX CHROMOSOME.

CELL DIVISION

PROKARYOTES HAVE A CIRCULAR
CHROMOSOME WHICH IS COPIED
INTO TWO CHROMOSOMES AND
SPLIT INTO TWO NEW CELLS
THROUGH BINARY FISSION.
EUKARYOTES DIVIDE ROD-SHAPED
CHROMOSOMES BY MITOSIS.
 THIS IS ASEXUAL REPRODUCTION.
 CYTOKINESIS DIVIDES THE CELL’S
CYTOPLASM.

THE CELL CYCLE
INTERPHASE IS
COMPRISED OF THE
FOLLOWING:
 G1 PHASE - OFFSPRING
CELLS GROW TO FULL
SIZE.
 S PHASE - DNA IS COPIED.
 G2 PHASE – THE CELL
PREPARES TO DIVIDE.

THE CELL CYCLE CONT.
MITOSIS IS COMPRISED OF THE
FOLLOWING:
 PROPHASE – REPLICATED
CHROMOSOMES EACH MADE UP OF
TWO CHROMATIDS FORM. A
MITOTIC SPINDLE FORMS MADE UP
OF CENTRIOLES, KINETOCHORE
FIBERS, AND POLAR FIBERS. ITS JOB
IS TO DIVIDE THE CHROMOSOMES.

METAPHASE – CHROMOSOMES
ALIGN AT THE CENTER OF THE CELL.
 ANAPHASE – CHROMATIDS OF EACH
CHROMOSOME ARE SEPARATED.
THEY ARE NOW CONSIDERED TO BE
INDIVIDUAL CHROMOSOMES.


TELOPHASE – CHROMOSOMES ARE
AT OPPOSITE ENDS OF THE CELLS. A
NUCLEAR MEMBRANE FORMS
AROUND EACH NEW GROUP OF
CHROMOSOMES TO FORM NEW
NUCLEI. THE CHROMOSOMES TURN
INTO CHROMATIN. THE SPINDLE
DISSOLVES. A NUCLEOLUS FORM IN
EACH NEW NUCLEUS.
CYTOKINESIS
THIS IS THE DIVISION OF THE
CYTOPLASM.
 A CLEAVAGE FURROW DEVELOPS IN
ANIMAL CELLS AND DIVIDES INWARD
FORMING TWO NEW CELLS.
 A CELL PLATE DEVELOPS IN PLANTS
CELLS. IT GROWS AT THE MIDLINE
DIVIDING THE CELL INTO TWO NEW
CELLS.

CONTROL OF CELL
DIVISION

CELL GROWTH (G1)
CHECKPOINT: PROTEINS
TELL THE CELL TO
EITHER GO TO THE S
PHASE TO COPY DNA OR
TO NOT DO THIS
BECAUSE CONDITIONS
ARE NOT SUITABLE.
SOME CELLS GO TO THE
G0 PHASE AND DO NOT
DIVIDE.

DNA SYNTHISIS (G2) CHECKPOINT: DNA
REPAIR ENZYMES CHECK THE COPIED
DNA. IF ALRIGHT, MITOSIS BEGINS.

MITOSIS CHECKPOINT: PROTEINS TELL
THE CELL TO EXIT MITOSIS AND GO THE
G1 PHASE AGAIN.
CANCER
PROTEINS ARE PRODUCED BY
GENES. IF GENES ARE MUTATED IN
A HARMFUL WAY, MALFUNCTIONING
PROTEINS DO NOT REGULATE THE
CELL GROWTH AND DIVISION.
 OUT OF CONTROL CELL GROWTH
AND DIVISION IS CANCER.

MEIOSIS
HAPLOID GAMETES (SPERM & EGG
CELLS) FORM.
 SPERM CELL (23 CHROMOSOMES) +
EGG CELL (23 CHROMOSOMES) =
HUMAN ZYGOTE (46
CHROMOSOMES)- THIS IS SEXUAL
REPRODUCTION

MEIOSIS I
PROPHASE I:
 CHROMOSOMES FORM
 TETRADS, PAIRS OF
HOMOLOGOUS
CHROMOSOMES, PAIR UP IN
SYNAPSIS.
 CROSSING OVER OCCURS
WHICH CAUSES GENETIC
RECOMBINATION.
 GENETIC VARIATION MAY
LEAD TO ENVIRONMENTAL
ADAPTATION.

METAPHASE I:
 TETRADS (HOMOLOGOUS PAIRS OF
CHROMOSOMES) LINE UP ALONG
THE MIDLINE OF THE CELL IN A
RANDOM ORDER CALLED
INDEPENDENT ASSORTMENT . THIS
GIVES GENETIC VARIATION.

ANAPHASE I:
 HOMOLOGOUS CHROMOSOMES,
EACH WITH A PAIR OF
CHROMATIDS, MOVE TO OPPOSITE
POLES OF THE CELL.

TELOPHASE I & CYTOKINESIS:
 CHROMOSOMES ARE AT THE
OPPOSITE POLES OF THE CELL.
 CYTOKINESIS SPLITS ONE CELL
INTO TWO HAPLOID CELLS.
 MEIOSIS II SPLITS TWO HAPLOID
CELLS INTO 4 HAPLOID CELLS

GAMETE DEVELOPMENT
SPERMATOGENESIS: SPERM
(SPERMATOZOA) FORMATION IN THE
TESTES.
 OOGENESIS: EGG (OVUM) FORMATION
IN THE OVARIES. THE THREE POLAR
BODIES DIE.

CELL REPRODUCTION TEST: CHAPTER 4
100 Points Total- Tuesday
Part I. Multiple Choice. 34 questions @ 2 points
each- Directly from notes
Part II. Matching. 16 questions identifying the
steps of mitosis and meiosis- coloring plates
#65-66