8/8/2019 003b Mitosis

1/67

8/8/2019 003b Mitosis

2/67

8/8/2019 003b Mitosis

3/67

8/8/2019 003b Mitosis

4/67

Rod shaped structure

Made of a single DNA molecule and

proteins called histones

Histones maintain shape of chromosomes

Aids in tight packing of DNA Seen during cell division

Coiled and compact

8/8/2019 003b Mitosis

5/67

DNA and Chromosomes

double-stranded

DNA molecule

8/8/2019 003b Mitosis

6/67

c t r r

l s

c r s s

centromere

homologous

chromosomes

8/8/2019 003b Mitosis

7/67

DNA

Replication

8/8/2019 003b Mitosis

8/67

Chromosome consists of two

identical halves

Each half is a chromatidFormed when DNA makes a copy of itself

before cell division

Each new cell will receive one chromatid

from each chromosome

Chromatids are held together by a

centromere

8/8/2019 003b Mitosis

9/67

sist r c r t i s

r lic t i

sister chromatids

DNA replication

8/8/2019 003b Mitosis

10/67

8/8/2019 003b Mitosis

11/67

23pairs

Sexchromosomes

autosomes

8/8/2019 003b Mitosis

12/67

8/8/2019 003b Mitosis

13/67

8/8/2019 003b Mitosis

14/67

Interphase- 75% of cell life cycle

G1: rapid growth

S: DNA replicates; centriolesreplicate.

G2

: cell prepares for cell division;microtubular structures form.

8/8/2019 003b Mitosis

15/67

Cell Division

Mitosis: cell divides its nuclearcomponents (chromosomes).

Cytokinesis: cell divides its

cytoplasmic components.

8/8/2019 003b Mitosis

16/67

Prophase

MetaphaseAnaphase

Telophase

8/8/2019 003b Mitosis

17/67

centrioles

chromatin

plasma

membrane

nucleolusnuclear

envelope

8/8/2019 003b Mitosis

18/67

Chromosomes shorten and become

visible (early prophase)Chromosomes made up of2 identical

chromatin threads called chromatids

Centrioles migrate toward opposite polepulled by kinetochore

Nuclear envelope disintegrates (late

prophase).

8/8/2019 003b Mitosis

19/67

centromere

chromosome

aster

centrioles

8/8/2019 003b Mitosis

20/67

asterpolar fiber

chromosomal

fiber

fragmenting

nuclearenvelope

8/8/2019 003b Mitosis

21/67

centrioles

nucleus

8/8/2019 003b Mitosis

22/67

Chromosomes lined up in the

middle

Mitotic spindle complete.

8/8/2019 003b Mitosis

23/67

metaphase plate

spindle

8/8/2019 003b Mitosis

24/67

polar fiberschromosomal

fibers

sister chromatids

8/8/2019 003b Mitosis

25/67

Chromosome at Metaphase

8/8/2019 003b Mitosis

26/67

Sister chromatids (= identical strands ofDNA) split from each other to form dividedidentical chromosomes.

Kinetochore fibers shorten and pull dividedidentical chromosomes to opposite sides of

the dividing cell.Polar microtubules slide past each other,

lengthening and pushing the cell apart

8/8/2019 003b Mitosis

27/67

daughter

chromosomes

8/8/2019 003b Mitosis

28/67

8/8/2019 003b Mitosis

29/67

Divided chromosomes reach opposite

sides of cell and begin to disperse as

chromatin.

Nuclear envelopes reforms around

separated collections of chromosomes to

form two nuclei.Cytokinesis- completion of cell division

8/8/2019 003b Mitosis

30/67

Spindle apparatus disintegrates.Cytokinesis usually begins near the

end of telophase.

8/8/2019 003b Mitosis

31/67

8/8/2019 003b Mitosis

32/67

Separation of cytoplasmiccomponents to yield two daughter

cells

Microfilaments form a contractingring that pinches the plasma

membrane inward between theforming daughter cells

8/8/2019 003b Mitosis

33/67

cleavage furrow

8/8/2019 003b Mitosis

34/67

8/8/2019 003b Mitosis

35/67

RNA

8/8/2019 003b Mitosis

36/67

Contrasting RNA with DNA

Single-stranded

Ribose

Bases

Adenine

UracilGuanine

Cytosine

Double-stranded

DeoxyriboseBases

AdenineThymineGuanineCytosine

RNA DNA

8/8/2019 003b Mitosis

37/67

mRNA- copies DNA and directs

protein synthesis

rRNA- joins with ribosomal

proteins to make ribosomes

tRNA- transfers amino acids toribosomes to make protein

8/8/2019 003b Mitosis

38/67

1. Transcription-occurs in nucleus mRNA copies DNA nucleotide

sequence

2. Translation

nucleotide sequence in mRNA is

uncoded

mRNA binds to rRNA tRNA brings appropriate amino acid to

mRNA

Polypeptide is manufactured

8/8/2019 003b Mitosis

39/67

8/8/2019 003b Mitosis

40/67

DNA

SenseStrand

mRNA

Transcript

8/8/2019 003b Mitosis

41/67

enzyme

mRNA

Transcription

begins here

8/8/2019 003b Mitosis

42/67

mRNA

8/8/2019 003b Mitosis

43/67

anticodon

codon

tRNA

8/8/2019 003b Mitosis

44/67

Ribosome

Amino Acid

tRNA

mRNA Codon Anticodon

8/8/2019 003b Mitosis

45/67

Initiator codon

Anticodon

AA

Binding sites

Ribosome

mRNA

8/8/2019 003b Mitosis

46/67

8/8/2019 003b Mitosis

47/67

8/8/2019 003b Mitosis

48/67

8/8/2019 003b Mitosis

49/67

8/8/2019 003b Mitosis

50/67

8/8/2019 003b Mitosis

51/67

Stop codon

AA

1

AAAA

T A G

A U C

2

AA

Complete protein

8/8/2019 003b Mitosis

52/67

Rapid and uncontrollable

development and production of cells.

8/8/2019 003b Mitosis

53/67

1. Inheritance may increase risk2. Proto-oncogenes and tumor suppressor

genes mutate or become damaged by

carcinogens

3. Known carcinogens:

Viruses and bacteria

Environmental chemicals

Tobacco Radiation

Dietary factors

8/8/2019 003b Mitosis

54/67

Conversion begins with a mutation(a change in DNA) by:

1. Chemical

2. Physical

3. Biological Conversion

8/8/2019 003b Mitosis

55/67

Development and Progression

8/8/2019 003b Mitosis

56/67

Begins when a chemical substance

stimulates growth of a mutated cell

Those chemical substances

influence a 2nd stage of

carcinogens called promoters.

Promoters stimulate cell to divide

uncontrollably Metastasis- cancer traveling to

other sites; like a forest fire

8/8/2019 003b Mitosis

57/67

8/8/2019 003b Mitosis

58/67

8/8/2019 003b Mitosis

59/67

8/8/2019 003b Mitosis

60/67

ozone

8/8/2019 003b Mitosis

61/67

Screens out 99% of harmful UV light Ozone produced by lightening

1% in ozone will result in a 2% in

skin cancerHoles in ozone:

Dupont- CFCs: hairspray, refrigerators,

air conditioning

Which country has the highest rate of

skin cancer?

8/8/2019 003b Mitosis

62/67

1. Avoid sun between 10am to 4pm.

2. Wear sunscreen w/ SPF 40+.

3. Wear appropriate clothing.

8/8/2019 003b Mitosis

63/67

Genetic testing

Biopsy

Blood test

X-rays, PET, MRI

V

isual & tactile observation

8/8/2019 003b Mitosis

64/67

Surgery

Radiation

Chemotherapy

Homeopathy

8/8/2019 003b Mitosis

65/67

Know family history Get regular medical screenings

Learn self-exam techniques

Avoid direct sunlight

Watch your diet and weight

Dont smoke

Drink alcohol in moderation (alcohol

decrease heart disease, but increasesrisk of certain cancers)

Become educated

INQUIRY

8/8/2019 003b Mitosis

66/67

INQUIRY

1. What do CFCs do?

2. What is a proto-oncogene?3. Name 3 carcinogens.

4. What are the ABCDs of skin cancer?

5. What is the function of ozone?6. Who is Henrietta Lacks?

8/8/2019 003b Mitosis

67/67

INQUIRY

1. Which cells in the body are diploid and which

are haploid?2. During which stage does DNA replication

occur?

3. Which stage of mitosis is seen in this picture?

4. At which stage is the cell binuclear?

5. In which phase do chromosomes line up in the

center of the cell?

6. Where does the kinetochore attach?