Ch 8.2 Cell Growth and Reproduction

Ch 8.2 Cell Growth and Reproduction

Hickox: Baker High School Biology

Ch 8.2 Cell Growth and Division

Opening Question:When a baby grows, what happens to his or her cells?

1)Does each of the cells get larger too?2) Are there more cells?

The Cells Divide rather than grow larger!3) The volume increases faster than the surface

area4) Homeostasis is disrupted by a cell that is too

large!


Ch 10 Cell Growth and Division

Cell Division5) Before the cell becomes too large, it

divides forming two ___________ cells.6) Before cell division, all of the ______

replicates or copies itself.


7) Two reasons cells divide rather than grow in size8) The __________ increases faster than the _________________9) ________________ is disrupted by a cell that is too large!

Ch 10 Cell Growth and Division

Remember from cell theory:10) All cells come from ___________

cells!11) This is _____ division, or

__________, these two cells that are identical to the original _________ cell

12 The exact copy of the parent is called a ___________ cell.


Ch 8-2 Cell Division

13)In eukaryotic cells, the ________ information is passed on from one generation to the next generation by strands of DNA called ___________ Most of a cell’s lifetime, chromosomes exist as Chromatin, granular material in the nucleus

14)Chromosomes are made up of _______, which carries the cells genetic information and proteins 15)Humans have ______ chromosomes or ___pairs16)Chromosomes are not visible except during cell

division17)Before cell division the chromosomes condense into

compact, visible structures that can be seen (compound light microscope)


The Cell Cycle

Chapter 10

MEIOSIS

GAMETES(sex cells)Egg and sperm

*There are _______ types of cell division…

MITOSIS produces exact copies of the__________ These cells are called _____________ cells



18. Draw the Chromosome Structure as shown on page 205. Include by labeling the following terms: Sister Chromatids, Centromere, and Chromosome

8- 2 The Cell Cycle

8.2

CHROMOSOME

CHROMATID

SISTER CHROMATIDS

CENTROMERE

“Structure” TETRADHickox: Baker High School Biology

Duplicated Chromosomes


19) A Tetrad: consists of two (2) homologous chromosomes, each made up of two sister

chromatids. The chromatids in a tetrad pair coil tightly and allow for crossing over (only in

meiosis).

8 – 2 Mitosis: Cell

8.2

Mitosis

20) Parent cell produces two daughter cells.

21) Each daughter cell gets a copy, thus each daughter cell is genetically identical to each

other and to the parent cell22) Mitosis is made up of several

phases:23) Prophase

24) Metaphase25) Anaphase26) Telophase

Mitosis starts with chromosomes doubling and condensing

During mitosis, sister chromatids separate and are identical to each other and to parent cell.


Ch 8.2 Cell Cycle

The Cell Cycle23) The “in-between” periods of cell growth are

called ___________.24) The cell _________ is the series of events that

cells go through as they grow and divide.


During Interphase:25) The cell grows in size and carries

on metabolism.

26) Chromosomes are duplicated!

Prophase

8.2

27) Prophase - The Preparation Phase (longest phase)

28) Chromosomes become visible29) Chromosomes are coiled tightly.30) Nucleolus disappears31) CENTRIOLES appear with spindle

fibers.32) SPINDLE forms a microtubule

structure that helps separate chromosomes

33) This is the first time __________ can be seen using a compound light microscope.


F


Metaphase: Second stage of Mitosis

8.2

Metaphase 34) (movement to equator)

35) Chromosomes line up along an imaginary plane called the

midline or equator.36) Chromosomes are pulled

by the spindle fibers and begin to line up on midline

or equator.37) Centrioles complete

migration to opposite poles


F


Anaphase: The third phase of mitosis

8.2

Anaphase (38) ( separation)

39) Centromeres split and the sister chromatids are pulled towards

opposite poles of the cell

40) Spindle fibers shorten pulls them apart

41) The two groups near the poles of the spindle


F


Telophase: the fourth phase of mitosis

8.2

Telophase 42) Chromatids reach the

opposite poles of the cell43) Chromosomes unwind and

begin metabolism.44) Spindle begin to break

down45) New Nuclear membrane

form


F


Cytokinesis

8.2

46) CYTOKINESIS: the cell’s cytoplasm divides into two

daughter cells.47) Typically occurs immediately

after mitosis48) In animals CLEAVAGE

FURROW49) In plants CELL PLATE


Cytokinesis in Animal Cells


Phases of Mitosis in Plant Cells


Mitosis & Cytokinesis

8.2Hickox: Baker High School Biology

Ch 8 -3 Regulating the Cell Cycle


An Overview of Meiosis and Mitosis


50) Meiosis is the process that produces sex cells, the _______ in males and the _________ in females.

sperm(1n)

egg(1n)

Zygote(2n)


51) During Meiosis the number of chromosomes is reduced by half. This chromosome number is called __________ (half) or ______.52) A diploid cell is a ____________ cell. (skin cells, nerve cells, muscle cells, etc)53) A haploid cell contains only one of each kind of ___________. A __________, or sex cell, is a haploid cell (eggs and sperms)54) Every living thing has a set number of chromosomes. For example, every has 78 chromosomes, Every person has 46 chromosomes and every tomato plant has 24 chromosomes The number of chromosomes does not relate to how complex an organism is



55) When organisms reproduce, it only passes on _________ the number of chromosomes.56) In a diploid cell, the two chromosomes of each pair are called ____________ ________

sperm(n)

egg(1n)

Zygote(2n)

Homologous Pairs57) Homologous chromosomes (homologues)

are paired chromosomes that code for the same traits (one inherited from each

(58) parent).


How does a diploid cell become a haploid cell


59) _____________ produces gametes containing ______the number of chromosomes as the parent’s body.60) Meiosis is actually _______ separate division, ______ and ____________.61) The whole process begins with one diploid cell (2n) and ends with _____ haploid cells. The haploid cells are gametes. When the egg and sperm unites the _______ becomes a multicellular organism, in a process called _________ reproduction

The Phases of Meiosis62) Before meiosis begins, the chromosomes in a cell are

replicated or copied. Each chromosome consist of ______ sister chromatids connected by a __________

Interphase: cell growth (2n) has nucleolus


Prophase I:• DNA coils up and spindle

forms• Chromosomes pair up


Prophase I:

Metaphase I: move to middle along equator

63) Crossing Over: Pieces of chromatid can break off from the other homologous chromosome and genetic information can be exchanged. Genetic Recombination

Crossing-Over


Meiosis I


Anaphase I: separation

Telophase I: spindle fibers break down and chromosomes uncoil, now there are two cells both (2n) diploid number.

Meiosis II:(second division)


Prophase II:Spindle forms in each new cell, attaches to centromere of chromosomes

Metaphase II:Movement to midline


Anaphase II:Separation and movement to poles

Telophase II;Cytoplasm separates and now there are four daughter cell with haploid number of chromosomes

Meiosis II:(second division)

Meiosis Overview


2n 2n

n n

Cell Cycle

39

Ch 8 -3 Control of the Cell Cycle


Normal Control of the Cell Cycle

• The cell cycle is controlled by conditions both inside the cell and in the cell’s environment. When something goes wrong with normal cell conditions, cells lose control of the cell cycle.

• Cancer is a growth that occurs when uncontrolled cell division take place.

• The loss of control may be caused by a change in enzyme production inside the cell or outside conditions , such as air or water pollution.

• Enzyme: type of protein that changes the rate of chemical reactions

Cancer: A mistake in the Cell Cycle


Scientists think cancer is caused by changes to one or more of the genes that control the cell cycle.A gene is a part of the DNA that controls the production of a protein.Cancer occurs when something causes the damaged genes to go into action (SMOKING). Cancer cells then form masses of tissues called tumors. Tumors keep normal cells from getting needed nutrients. This caused organ damage. Cancer can spread throughout the body to other organs.

Lung Cancer (smoker)

Clean Lung (non-smoker)

What are the causes of cancer?


Cancer is the second leading cause of DEATH in the United States. Environmental factors include:• cigarette smoke• air and water pollution• exposure to ultraviolet radiation from sun• viral infections that damage the genes

Lung Cancer (smoker)

Skin cancer(sun exposure)

Cytokinesis

Cleavage furrow

Animals only, not plants!


CentrisomeSpindle fibers

Prophase

Chromosomes-Thicken, double, are visible, nucleolus and nuclear membrane disappear

Interphase – cell growth


Anaphase:


Prophase:


Metaphase:


Telophase:Hickox: Baker High School Biology

Prophase:


1.

2.

3.

4.

5.


Hickox: Baker High School Biology Mitosis

1. 2. 3.

4. 5. 6.


Meiosis I

Meiosis II


Ch 8.2 Cell Growth and Reproduction

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Transcript of Ch 8.2 Cell Growth and Reproduction