Mitosis Under what circumstances do cells undergo mitosis? What happens within and to a cell during the cell cycle? What happens to a cell when it is not actively dividing? What are some of the ways in which mitotic rate and the number of divisions are controlled?

Big Ideas (continued) 5. How do the growth properties of cancer cells reflect a loss of control of mitosis? 6. What are the characteristics of cancer cells? How can genes that normally control the cell cycle cause cancer? What are some factors that might contribute to causing cancer?

Science Notebooks In- Out- Through Date1/19 Chapter 3 Review-page 90 questions 9-16 Out- Why is mitosis important? Through Date1/19 Summary

Science Notebooks In- Out- Through Date1/19 Chapter 3 Review-page 90 questions 9-16 Out- Why is mitosis important? Through Date1/19 Summary

Through Review parts of the cell Cell processes worksheet Review quiz Previewing Chapter 4 if time

Previewing the Text Skim section 1 of your book. Read the headings, illustrations, and captions. Write three (3) questions that come to mind as you skim the section.

My Three Questions? Why do cells divide? What is mitosis? What is asexual reproduction?

What is Mitosis? (section 1) Mitosis is the process in which the nucleus divides to form two identical nuclei. It is described as a series of phases or steps.

FYI The bacterium Escherichia coli divides every 20 minutes. This means that, three times every hour, a population of these tiny organisms can double. If a single E. coli cell had unlimited nutrients and space, and divided every 20 minutes, it would produce a colony of approximately 5,000,000,000,000,000,000,000 (5 w/21-zeros) in just a day. After a day and a half, that first cell would have produced enough offspring to cover the entire planet in a 1-foot-thick coating.

Why mitosis (cell division)? B.I. – (section 1) Mitosis Provides Growth, Replacement, Repair, and Reproduction

Cell Reproduction ~~ IN- What is the difference between Cell Division and Mitosis? OUT- Give two examples of asexual reproduction in many-celled organisms.

*Cell Cycle* Individual cells like other things have a “life cycle”, it is a series of events that takes place from one cell division to the next. (section 1)

*Cell Cycle* Individual cells like other things have a “life cycle”, it is a series of events that takes place from one cell division to the next. (section 1) Interphase It is the longest part of the cell cycle. Cells grow and develop Copy their DNA and prepare for cell division. (cells no longer dividing are always in interphase)

2. Prophase Chromatid pairs are now visible and the spindle is beginning to form.

6ish Steps of Mitosis-continued 3. Metaphase 4. Anaphase Chromatid pairs are lined up in the center of the cell The chromosomes have separated.

6ish Steps of Mitosis-continued The final step, the cytoplasm is beginning to separate. Two new cells are formed. 5. Telophase 6. Division of cytoplasm

Summary (out) Mitosis Cell Division

Asexual Reproduction ~~ IN- Identify 3 reasons why cell division is important!!!!!!! OUT- Mitosis is the division… (please finish the definition)

Science Notebooks In- What is a cell cycle and are all cycles the same length? Out- List 3-4 differences between a plant and animal cell. Topic: Plant vs animal cell Date: 01/22 Microscope lab- Summary- How well did I work with my lab partner? WERE YOU ABLE TO SEE THE CELLS? PLEASE FOLLOW YOUR PROCEDURES 19

Cell Reproduction 1/23 IN-In what ways have you grown in the wonderful year of 2017/18? OUT-What is the difference between cell division and mitosis?

Cell Common Assessment 1/24 IN- What is your prediction about how well you will do on the exam and WHY? OUT- What does- G- r- stand for or represent?

My toes is? 1/25 In- What are the four stages/phases of MITOSIS? Out- List and describe---The 3 forms of asexual reproduction . https://youtu.be/f-ldPgEfAHI

IN- How are cancer and mitosis related? MEIOSIS-1/26 IN- How are cancer and mitosis related? OUT- Which stage/phase of mitosis was most easily seen in the microscope today?

Important concepts about mitosis. (section 1) Mitosis is the division of a cell nucleus. Mitosis produces two new nuclei that are identical both to each other and to the original nucleus. A nucleus with 46 chromosomes that undergoes mitosis will produce two nuclei, each with 46 chromosomes.

The 3 forms of asexual reproduction . Binary fission- the method by which bacteria reproduce Budding- new organism growing from body of the parent Regeneration- to regrow body parts that are lost or damaged

IN-Why is meiosis needed for sexual reproduction? OUT- How many chromosomes are usually in each human sperm or egg? Jan 29

Meiosis vs. Mitosis IN- In order for animals to reproduce sexually they need to be from the same _____________. OUT- How does the chromosome number of our species stay the same from generation to generation during meiosis?  1/30

Meiosis 1/31 IN-How many chromosomes does each new cell contain after mitosis if the original cell had 52 original chromosomes, and why? OUT- What types of cells in your body are no longer undergoing mitosis? What phase of the cell cycle are those cells in?

While you read (find it-write it-leave it-we will check it) Meiosis Definition ___________________ Where it occurs Where it doesn’t occur Summary

Sexual Reproduction and Meiosis (section 2) Sexual reproduction- two sex cells, called and egg and a sperm, come together. Sperm are formed in the male reproductive organs. Eggs are formed in the female reproductive organs. Zygote- is a cell that forms from fertilization. Following fertilization, cell division begins and a new organism develops.

So What’s The Diff?

Types of Human Cells Diploid Haploid 46 23 mitosis meiosis Examples (cell whose similar chromosomes occur in pairs) Haploid (cells that have only half of each pair of chromosomes) Number of chromosomes 46 23 Process that produces them mitosis meiosis Examples brain, skin, and bone cells egg and sperm cells

Meiosis and Sex Cells (meiosis-reproductive process that produces haploid cells) Meiosis I Prophase I pairs of duplicated chromosomes together nuclear membrane disappearing spindle is forming Metaphase I Pairs of duplicated chromo- somes lined up in center of cell centromeres attached to single spindle fibers Anaphase I duplicated chromosomes moving to opposite ends of the cell Telophase I cell cytoplasm beginning to divide one duplicated chromosome from each pair in each half

Meiosis and Sex Cells (section 2) Meiosis II Prophase II pairs of duplicated chromosomes spindle is forming Metaphase II duplicated chromosomes moving to the center of the cell two spindle fibers attaching to each centromere Anaphase II the chromatids are separating and moving to opposite ends of the cell Telophase II spindle fibers disappearing nuclear membranes forming around the chromosomes at each end of the cell

Differences between Meiosis I and Meiosis II How many cells result? Is a haploid cell formed? Do chromatids separate?

Differences between Meiosis I and Meiosis II How many cells result? 2 4 Is a haploid cell formed? Do chromatids separate?

Differences between Meiosis I and Meiosis II How many cells result? 2 4 Is a haploid cell formed? NO YES Do chromatids separate?

Differences between Meiosis I and Meiosis II How many cells result? 2 4 Is a haploid cell formed? NO YES Do chromatids separate?

Importance of Meiosis? Meiosis ensures that offspring produced by fertilization have the same number of chromosomes as their parents. ~If the diploid number of a frog is 26, how many chromosomes does the tadpole have?

DNA IN- How are sex cells different from other cells in the body? OUT- Write the letter of the DNA bases that pair with the following DNA strand. T: G: A: C:

In- What is the difference between a dominant and recessive trait…give an example. OUT- Explain how dominant & recessive traits are represented in a Punnett square.

Comparison of Mitosis and Meiosis One division Two daughter cells per cycle Chromosome number of daughter cells same as that of parent cell (2n) Occurs in somatic cells Occurs throughout life cycle Use for growth, development, repair, and reproduction Two divisions Four daughter cells/ cycle (Daughter cells genetically different) Chromosome number of daughter cells half that of parent cell (n) Occurs in sex cells In human, completed only after sexual maturity Used for sexual reproduction, in which new gene combinations arise

Comparison of Mitosis and Meiosis One division Two daughter cells per cycle Chromosome number of daughter cells same as that of parent cell (2n) Occurs in somatic cells Occurs throughout life cycle Use for growth, development, repair, and reproduction Two divisions Four daughter cells/ cycle (Daughter cells genetically different) Chromosome number of daughter cells half that of parent cell (n) Occurs in sex cells In human, completed only after sexual maturity Used for sexual reproduction, in which new gene combinations arise

Comparison of Mitosis and Meiosis One division Two daughter cells per cycle Chromosome number of daughter cells same as that of parent cell (2n) Occurs in somatic cells Occurs throughout life cycle Use for growth, development, repair, and reproduction Two divisions Four daughter cells/ cycle (Daughter cells genetically different) Chromosome number of daughter cells half that of parent cell (n) Occurs in sex cells In human, completed only after sexual maturity Used for sexual reproduction, in which new gene combinations arise

Comparison of Mitosis and Meiosis One division Two daughter cells per cycle Chromosome number of daughter cells same as that of parent cell (2n) Occurs in somatic cells Occurs throughout life cycle Use for growth, development, repair, and reproduction Two divisions Four daughter cells/ cycle (Daughter cells genetically different) Chromosome number of daughter cells half that of parent cell (n) Occurs in sex cells In human, completed only after sexual maturity Used for sexual reproduction, in which new gene combinations arise

Comparison of Mitosis and Meiosis One division Two daughter cells per cycle Chromosome number of daughter cells same as that of parent cell (2n) Occurs in somatic cells Occurs throughout life cycle Use for growth, development, repair, and reproduction Two divisions Four daughter cells/ cycle (Daughter cells genetically different) Chromosome number of daughter cells half that of parent cell (n) Occurs in sex cells In human, completed only after sexual maturity Used for sexual reproduction, in which new gene combinations arise

Comparison of Mitosis and Meiosis One division Two daughter cells per cycle Chromosome number of daughter cells same as that of parent cell (2n) Occurs in somatic cells Occurs throughout life cycle Use for growth, development, repair, and reproduction Two divisions Four daughter cells/ cycle (Daughter cells genetically different) Chromosome number of daughter cells half that of parent cell (n) Occurs in sex cells In human, completed only after sexual maturity Used for sexual reproduction, in which new gene combinations arise