Cell Reproduction cell division What is cell division

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Cell Reproduction (cell division)

Cell Reproduction (cell division)

What is cell division? p 96 1. 2. Cell division is the process by

What is cell division? p 96 1. 2. Cell division is the process by which a parent cell divides into two or more daughter cells. Cell division usually occurs as part of a larger cell cycle

Why do cells divide/reproduce? 1. 2. For organism growth, repair, and replacement of dead

Why do cells divide/reproduce? 1. 2. For organism growth, repair, and replacement of dead cells AND asexual reproduction (GRRR) To maintain a workable cell to surface area ratio. (too big, DNA/nucleus can’t manage all the material)

What does cell division for growth & repair look like? n One cell with

What does cell division for growth & repair look like? n One cell with 2 sets of chromosomes makes 2 cells with the same # of chromosomes=2 N or two sets

What are two types of reproduction that use cell division? 1. 2. Asexual reproduction

What are two types of reproduction that use cell division? 1. 2. Asexual reproduction of genetically IDENTICAL (clones) offspring from one parent Sexual production of genetically DIFFERENT offspring from two parents

Unicellular Organisms divide 1 cell for Use Asexual reproduction of genetically IDENTICAL (clones) offspring

Unicellular Organisms divide 1 cell for Use Asexual reproduction of genetically IDENTICAL (clones) offspring from one parent EX: n Binary fission- cells splits into two. Used by all bacteria n Spores- form a protective wall and remain inactive until conditions favorable n Budding- cell pinches off from parent to form new individual

Multicellular organisms Use Asexual production of genetically IDENTICAL offspring/tissue from one parent n n

Multicellular organisms Use Asexual production of genetically IDENTICAL offspring/tissue from one parent n n Vegetative Propagation- occurs in plants where part of the plant is allow to develop into a whole new plant. Ex. Onion plants grow from stem of onion Regeneration- the re-growing of a part of an organism when it is cut off and removed from that organism. Ex. Starfish regrows missing arm

Multicellular organisms Sexual production of genetically DIFFERENT offspring from two parents n n Step

Multicellular organisms Sexual production of genetically DIFFERENT offspring from two parents n n Step 1: Meiosis/making sex cells=sperm and egg involves reducing the DNA in half EX: 2 N / 2= N Step 2: Fertilization/joining the sex cells - involves combining two half sets of DNA to create one full set EX: N+N = 2 N

What does cell division for making sperm and egg look like? n One cell

What does cell division for making sperm and egg look like? n One cell with 2 sets of chromosomes makes 4 cells with half the # of chromosomes=N or one set

What does fertilization look like? n One sperm and one egg each with 1

What does fertilization look like? n One sperm and one egg each with 1 set of chromosomes =N join to form a unique cell (zygote=fertilized egg)

Ssexual reproduction involves Meiosis AND Fertilization/joining the sex cells-

Ssexual reproduction involves Meiosis AND Fertilization/joining the sex cells-

Critical Questions 1. Name 3 reasons that cells must divide n 1. Growth n

Critical Questions 1. Name 3 reasons that cells must divide n 1. Growth n 2. Repair damaged cells n 3. Replace dead cells 2. Which type of asexual reproduction would bacteria (a unicellular organism) use? n Binary 3. Fission After cells divide asexually, are they exact clones of each other? n YES

What makes up a cell? p 98 Cells contain a nucleus. The nucleus has

What makes up a cell? p 98 Cells contain a nucleus. The nucleus has chromosomes inside. Chromosomes are made up of DNA has instructions that all cells need

What is the cell cycle? 1. The cell cycle or celldivision cycle is the

What is the cell cycle? 1. The cell cycle or celldivision cycle is the series of events that include v v v 2. DNA replication AND Mitosis: division of the DNA & organelles that produces two daughter cells. Cytokinesis divides cytoplasm Cell division usually occurs as part of a larger cell cycle

https: //www. youtube. com/watch? v=rg. LJrvo. X_qo

https: //www. youtube. com/watch? v=rg. LJrvo. X_qo

Label the parts of the Cell cycle: § G 1: growth § S: DNA

Label the parts of the Cell cycle: § G 1: growth § S: DNA replication § G 2: growth & prepare for mitosis § M: prophase, metaphase, anaphase, telophase

1. Interphase 3 parts of the Cell Cycle n Growth and synthesis 2. Mitosis

1. Interphase 3 parts of the Cell Cycle n Growth and synthesis 2. Mitosis n Prophase n Metaphase n Anaphase n Telophase 3. Cytokinesis

https: //www. youtube. com/watch? v=3 Cfvm. WMz. F 2 A

https: //www. youtube. com/watch? v=3 Cfvm. WMz. F 2 A

1. Interphase: involves Growth and synthesis: cell matures and prepares for reproduction. n Replication

1. Interphase: involves Growth and synthesis: cell matures and prepares for reproduction. n Replication (DNA is copied) makes duplicate copies for 2 new cells n organelles & cytoplasm copied

2. Mitosis is the division of the cells nucleus n It has 4 phases

2. Mitosis is the division of the cells nucleus n It has 4 phases

https: //www. youtube. com/watch? v=C 6 hn 3 s. A 0 ip 0

https: //www. youtube. com/watch? v=C 6 hn 3 s. A 0 ip 0

What cell parts are involved in cell division? n Centrioles n Make the spindle

What cell parts are involved in cell division? n Centrioles n Make the spindle fibers n Chromosome n Made of coiled chromatin/DNA n Sister n Two chromatids copies of a chromosome

Label the cell parts involved in cell division: n Centriole n Spindle fiber n

Label the cell parts involved in cell division: n Centriole n Spindle fiber n Centromere n Chromosome n Sister chromatids

Prophase n n n Chromosomes appear Centrioles move to opposite poles Spindle fibers begin

Prophase n n n Chromosomes appear Centrioles move to opposite poles Spindle fibers begin to appear

Metaphase n n Chromosomes line up across the equator OR middle Spindle fibers attach

Metaphase n n Chromosomes line up across the equator OR middle Spindle fibers attach at the centromere

Anaphase n n Spindle fibers pull apart the two chromosomes Divided chromosomes move to

Anaphase n n Spindle fibers pull apart the two chromosomes Divided chromosomes move to the opposite poles

Telophase n n Two identical new nuclei are then formed Cytokinesis then begins to

Telophase n n Two identical new nuclei are then formed Cytokinesis then begins to occur

NOW…Label the phases of MITOSIS: n prophase n metaphase n anaphase n telophase

NOW…Label the phases of MITOSIS: n prophase n metaphase n anaphase n telophase

telophase metaphase Two new nuclei Chromosomes line up in middle Can you identify each

telophase metaphase Two new nuclei Chromosomes line up in middle Can you identify each phase? How can you tell each apart? prophase One nuclei, chromosomes visible Chromosomes move apart anaphase

3. Cytokinesis n Cytoplasm divides and two identical daughter cells are formed

3. Cytokinesis n Cytoplasm divides and two identical daughter cells are formed

https: //www. youtube. com/watch? v=AEt 8 V 53 odd. A

https: //www. youtube. com/watch? v=AEt 8 V 53 odd. A

How does cytokinesis differ in animal vs plant? Animal cell membrane pinches in and

How does cytokinesis differ in animal vs plant? Animal cell membrane pinches in and forms a cleavage furrow plant cell membrane and a cell plate forms into a new cell wall

Essential Questions n Why must the DNA be copied during interphase? n So there

Essential Questions n Why must the DNA be copied during interphase? n So there will be a complete set of chromosomes in each new cell n How do plant and animal cell division differ? n Plants form a cell plate, animals form a cleavage furrow. Animals have centrioles, plants do not.

https: //www. youtube. com/watch? v=p. Os. Ab. Ti 9 t. Hw

https: //www. youtube. com/watch? v=p. Os. Ab. Ti 9 t. Hw

Critical Thinking n Cancer is uncontrolled cell division. How is mitosis important to a

Critical Thinking n Cancer is uncontrolled cell division. How is mitosis important to a doctor studying cancer? n If a doctor knew how to stop mitosis in the cancer cells, then they would be able to stop the cancer from spreading to other parts of the body. This would then allow the doctors to remove the cancerous cells and save the patient

Mitosis in Onion root tip

Mitosis in Onion root tip

p 105 n n n Creates clones=copies Uses One parent/cell Produces 2 identical daughter

p 105 n n n Creates clones=copies Uses One parent/cell Produces 2 identical daughter cells Makes somatic=body cells Makes 2 diploid=2 N cells n n n Creates variation=differences Uses two parents Creates 4 different cells Makes gametes=sex cells Makes 4 haploid=N cells

Mitosis vs Meiosis p 105 n n n Creates clones=copies Uses One parent/cell Produces

Mitosis vs Meiosis p 105 n n n Creates clones=copies Uses One parent/cell Produces 2 identical daughter cells Makes somatic=body cells Makes 2 diploid=2 N cells For Asexual reproduction n n n Creates variation=differences Uses two parents Creates 4 different cells Makes gametes=sex cells Makes 4 haploid=N cells For sexual reproduction

Mitosis & Meiosis go through the same phases Interphase- DNA replication & growth Mitosis-

Mitosis & Meiosis go through the same phases Interphase- DNA replication & growth Mitosis- NUCLEUS divides 1 X Meiosis-divides 2 X n n n Prophase- sister chromatids PAIR UP n Metaphase-sister chromatids LINE UP n Anaphase- sister chromatids SEPARATE n Telophase- chromosomes form. TWO NUCLEI Cytokinesis-CYTOPLASM divides