07. cell division.ppt
TRANSCRIPT
-
8/14/2019 07. Cell division.ppt
1/48
Cell division: mitosis and meiosis
I. Dividing cellsII. Mitosis and the cell cycleIII. Stages of mitosis
A. ProphaseB. MetaphaseC. AnaphaseD. Telophase
IV. Stem cellsV. Telomeres and telomeraseVI. Cancer cellsVII. MeiosisVIII. Gametogenesis
-
8/14/2019 07. Cell division.ppt
2/48
Binary Fission- prokaryotes
-
8/14/2019 07. Cell division.ppt
3/48
Ploidy levels: diploid (2N) and haploid (1N)In mitosis, ploidy level is maintained
In meiosis, ploidy level is halved.
Human = 46
Chimpanzee = 48
Chicken = 78
Dog = 78
Record > 1000!
Meiosis, mitosis, and the chromosome number
-
8/14/2019 07. Cell division.ppt
4/48
II. Mitosis and the cell cycle
10 hours 8 hours
5 hours
1 hour
-
8/14/2019 07. Cell division.ppt
5/48
If a cell, like a red blood cell, were to stop dividing, what stage ofthe cell cycle would be terminal for that cell?
a. G1 b. G2 c. S d. mitotic
If a cell that was 4N at the start of meiosis, the end result wouldbe _______ cells .a. 1N b. 2N c. 3N d. 4N
-
8/14/2019 07. Cell division.ppt
6/48
III. Stages of mitosis
-
8/14/2019 07. Cell division.ppt
7/48
-
8/14/2019 07. Cell division.ppt
8/48
What is the ploidy of a cell in anaphase of mitosis?a. Haploid b. diploid c. triploid d. quatraploid
In what phase do chromosomes line up at the equator?a. metaphase b. anaphase c. prophase d. telophase
When attached together , what are the two replicated DNA strands ofa single chromosome called?a. centromeres b. chromosomes c. chromatids d. chromatin
-
8/14/2019 07. Cell division.ppt
9/48
MitosisMitosis animation
http://highered.mcgraw-hill.com/olc/dl/120073/bio14.swfhttp://highered.mcgraw-hill.com/olc/dl/120073/bio14.swf -
8/14/2019 07. Cell division.ppt
10/48
DNA before and after mitosis
-
8/14/2019 07. Cell division.ppt
11/48
-
8/14/2019 07. Cell division.ppt
12/48
Stem cell research
Adult stem cell research
Embryo stem cell research
-
8/14/2019 07. Cell division.ppt
13/48
Stem cell potential
Adult cell cloning
Incompatibility, ethics, and the law
-
8/14/2019 07. Cell division.ppt
14/48
IVF/ PGD and stem cell research
-
8/14/2019 07. Cell division.ppt
15/48
How does the PGD technique circumvent the ethical issuessurrounding the use of embryos in stem cell research?
a. it doesntb. embryos are not used in any way for this technique
c. embryos are not destroyedd. only dead embryos are used
What is the advantage of using embryonic stem cells over othertypes of stems cells?
a.They divide more quicklyb.There is less controversy in using themc.They are easier to work withd.They are more versatile
-
8/14/2019 07. Cell division.ppt
16/48
-
8/14/2019 07. Cell division.ppt
17/48
V. Telomeres and telomerase
TTAGGG
embryosstem cells
cancer cells
-
8/14/2019 07. Cell division.ppt
18/48
What exactly are telomeres?a. Caps at the ends of chromosomesb. An enzyme that allows cells to keep dividingc. A repeated sequence of nucleotides at the ends of chromosomesd. Structures found only in embryos
Which of the following cells do not have telomerase?a. Mature skin cellsb. Liver stem cellsc. Early embryonic cellsd. Cancer cells
-
8/14/2019 07. Cell division.ppt
19/48
VI. CancerA. Two types of tumors (neoplasms)B. Cancer cell anatomy and physiology
1. differentiation2. shape
3. embryonic proliferation4. non-programmed cell death
C. Genes and cancer1. oncogenes2. tumor suppressing genes
3. teleomerase
-
8/14/2019 07. Cell division.ppt
20/48
A. Two types of tumors (neoplasms)An inappropriate proliferation of cells
Neoplasms: two types
benign
malignant
Metastasis
-
8/14/2019 07. Cell division.ppt
21/48
B. Cancer cell anatomy and physiology
1. differentiation
2. shape
3. proliferation
4. Non-programmed cell death
5. Telomerase
-
8/14/2019 07. Cell division.ppt
22/48
C. Genes and cancer
1. oncogenes
2. tumor suppressing genes
3. Telomerase genesProgression of cancer
Stem cells, cancer, and aging
Ink4
http://www.nytimes.com/2006/09/07/science/07stem.html?_r=1&ref=science&oref=sloginhttp://www.nytimes.com/2006/09/07/science/07stem.html?_r=1&ref=science&oref=slogin -
8/14/2019 07. Cell division.ppt
23/48
What is the problem with enhancing the activity of Ink4?a. Increased risk of cancerb. Speeding up of the aging processc. Both a and b
d. Neither a or b
What are oncogenes?a. Genes that regulate cell divisionb. Genes that suppress tumorsc. Genes that reestablish telomeres
d. Mutated proto-oncogenes
-
8/14/2019 07. Cell division.ppt
24/48
VII. Meiosis
2. 2 goals: reducing the chromosome number by half andshuffling (recombining) the genes
1. Homologues/ homologous pairs
Why half?
A. Overview
-
8/14/2019 07. Cell division.ppt
25/48
Human Life Cycle
-
8/14/2019 07. Cell division.ppt
26/48
Meiosis I
Crossing over
IndependentAssortment
Meiosis II
http://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppt -
8/14/2019 07. Cell division.ppt
27/48
Crossing Over
-
8/14/2019 07. Cell division.ppt
28/48
Independent Assortment2n= number of unique gametes
http://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppthttp://localhost/var/www/apps/conversion/tmp/scratch_4/07.%20Cell%20division.ppt -
8/14/2019 07. Cell division.ppt
29/48
Meiosis II Meiosis animation
http://highered.mcgraw-hill.com/olc/dl/120074/bio19.swfhttp://highered.mcgraw-hill.com/olc/dl/120074/bio19.swf -
8/14/2019 07. Cell division.ppt
30/48
In what phases of meiosis do genetic recombination take place?a. Prophase I and Prophase IIb. Metaphase I and Anaphase Ic. Prophase II and Metaphase IId. Prophase I and Metaphase I
If an organism has 3 pairs of chromosomes, based on independentassortment, how many genetically unique gametes would it have?a. 3 b. 6 c. 8 d. 9
-
8/14/2019 07. Cell division.ppt
31/48
Problems in meiosis:aneuploidyNondisjunction and Trisomy: Anaphase II
-
8/14/2019 07. Cell division.ppt
32/48
Nondisjunction and Trisomy
Women over 35, 2 to 6 times the number of mutations
Most common trisomy is trisomy 21 (Down Syndrome)
Problems in meiosis
Implantation of embryo more likely
-
8/14/2019 07. Cell division.ppt
33/48
Trisomy 21: Down syndrome
Trisomy 21 karyotype
-
8/14/2019 07. Cell division.ppt
34/48
Klinefelters Syndrome
-
8/14/2019 07. Cell division.ppt
35/48
Turner Syndrome
Monosomy
-
8/14/2019 07. Cell division.ppt
36/48
Which of the following is the most accurate statement concerninganeuploidy?a. Nondisjunction of chromosomes during meiosisb. A condition in which there are not the correct number ofchromosomesc. Three chromosomes at position number 21d. The result of early implantation of the embryo
What would be the result of a nondisjunction in Anaphase I?a. Two normal gametes, one with an extra chromosome, and onemissing a chromosomeb. Two normal gametes, two with an extra chromosomec. Three gametes with a missing chromosome, one with an extrachromosomed. Two gametes with an extra chromosome, two with a missingchromosome
-
8/14/2019 07. Cell division.ppt
37/48
Meiosis compared to mitosis
Purpose
Number of cells produced
Genetics of cells produced
Ploidy of cells produced
Where they occur
Somatic cells Sex cells
-
8/14/2019 07. Cell division.ppt
38/48
Meiosis compared to mitosis
-
8/14/2019 07. Cell division.ppt
39/48
-
8/14/2019 07. Cell division.ppt
40/48
VIII. Gametogenesis
-
8/14/2019 07. Cell division.ppt
41/48
Spermatogenesis
Puberty
Average sperm production =100 million per day
-
8/14/2019 07. Cell division.ppt
42/48
-
8/14/2019 07. Cell division.ppt
43/48
Oogenesis
In embryo
At birth
Arrested atProphase I
Ovulation
Arrested at
Metaphase II
Meiosis completedat fertilization
Approximately 400, 000
400 released
-
8/14/2019 07. Cell division.ppt
44/48
When does oogenesis start in female mammals?a. At birthb. Before birthc. At puberty
d. At fertilization
When does oogenesis end in female mammals?a. At birthb. Before birth
c. At pubertyd. At fertilization
-
8/14/2019 07. Cell division.ppt
45/48
In oogenesis, what is the end result of interkinesis?a. Two secondary oocytesb. One secondary oocyte and one polar bodyc. One secondary oocyte and two polar bodiesd. Two secondary oocytes and two polar bodies
-
8/14/2019 07. Cell division.ppt
46/48
egg sperm
1. Haploid set of chromosomes 1. Haploid set2. X to males and females 2. X to females;
Y to males3. Protection
4. Nourishment
5. Directions for early development6. Mitochondria
Mutations?
Contributions of egg and sperm to embryo
-
8/14/2019 07. Cell division.ppt
47/48
Which of the following is a contribution of the sperm to the embryo?a. Mitochondriab. Directions for early developmentc. Protectiond. Nourishmente. Most mutations
The contribution of the sperm above is __________ .a. Beneficialb. Detrimental
c. Neutrald. Could be any or all of the above
-
8/14/2019 07. Cell division.ppt
48/48
The end