Cellular Basis of Inheritance Chapter 9: Cellular Basis of Inheritance

9.1 All Cells Come From Cells 9.1 All Cells Come From Cells

Why do cells reproduce? 1. Replace dead and worn-out cells Why do cells reproduce? 1. Replace dead and worn-out cells 2. Add new cells=growth 3. Reproduction of new organisms (to continue species)

Intro to Cell Reproduction Intro to Cell Reproduction

2 Types of Cell Reproduction 2 Types of Cell Reproduction Sexual Asexual

Asexual Reproduction

Asexual Reproduction Used in unicellular organisms Asexual Reproduction Used in unicellular organisms Offspring identical to parents Ex: Paramecium Some multicellular organisms can reproduce asexually!

Sexual Reproduction

Sexual Reproduction 2 parents involved Sexual Reproduction 2 parents involved Genetic material comes from each Occurs with a special form of cell reproduction New cells are NOT identical to parent cells

Vocab in 9.1 Asexual Reproduction Sexual Reproduction

The Cell Cycle Multiplies Cells Concept 9.2 The Cell Cycle Multiplies Cells

Chromosomes & Cell Division Chromosomes & Cell Division Genetic info is carried on chromosomes Chromatin is long and thin, not visible Chromosomes are short, thick & visible BEFORE cell division each chromosome is copied 2 copies=sister chromatids Centromere= holds copies together

Cell Cycle

Cell Cycle Length depends on cell type Some cells don’t divide… Cell Cycle Length depends on cell type Some cells don’t divide… Begins with “birth” of cell 2 Phases Interphase Mitotic Phase

Interphase

Interphase 90% of cell cycle time Performs daily functions Interphase 90% of cell cycle time Performs daily functions Prepares for cell division Broken into 3 parts: G1= Gap 1; growth and replication S= Synthesis; DNA duplicates G2= Gap 2; final preparations

Mitotic Phase

Mitotic Phase When cell is actual dividing 2 Phases Mitotic Phase When cell is actual dividing 2 Phases Mitosis=division of the nucleus Cytokinesis= division of everything outside nucleus Produces 2 identical cells Very accurate!

9.2 Vocab Chromatin Chromosome Centromere Sister chromatids Interphase 9.2 Vocab Chromatin Chromosome Centromere Sister chromatids Interphase Mitosis cytokinesis Cell cycle

Cells Divide During Mitotic Phase Concept 9.3 Cells Divide During Mitotic Phase

Remember… DNA has already copied Mitosis is a continual process Remember… DNA has already copied Mitosis is a continual process Broken into 4 Stages

Mitosis-Preview

Prophase

Prophase Chromatin becomes chromosomes=visible Nucleolus disappears Prophase Chromatin becomes chromosomes=visible Nucleolus disappears Nuclear membrane disappears Spindle fibers form

Metaphase

Metaphase Chromatids attach to spindle fibers Metaphase Chromatids attach to spindle fibers Chromatics move to line up in center

Anaphase Sister chromatids separate from each other Anaphase Sister chromatids separate from each other Each chromatid is now a chromosome Chromosomes move to poles

Telophase Chromosomes reach poles Reverse of Prophase Telophase Chromosomes reach poles Reverse of Prophase Spindle disappears 2 nuclear membranes form Chromosomes uncoil to chromatin Nucleolus reappear

Cytokinesis Division of cytoplasm and contents Cytokinesis Division of cytoplasm and contents Usually occurs along with telophase

Cytokinesis in Plant vs. Animal Cytokinesis in Plant vs. Animal Animal 1st sign is indentation in cell membrane Plant Can’t pinch so… New cell wall (cell plate) forms from center out

9.3 Vocab Spindle Centrosomes Centrioles Prophase metaphase Anaphase 9.3 Vocab Spindle Centrosomes Centrioles Prophase metaphase Anaphase Telophase Cytokinesis Cell plate

Cell Cycle & Mitosis Review Cell Cycle & Mitosis Review

Cancer cells grow and divide out of control… Concept 9.4 Cancer cells grow and divide out of control…

Cancer…

Tumors and Cancer Tumor= large mass of cells Tumors and Cancer Tumor= large mass of cells Benign tumor= consists of normal cells Surgery is an option Location may cause health problems Malignant tumor= consists of cancer cells Cancer= cells who’ve lost control of cell cycle Can lead to death Replace normal cells as they grow Metastasis=cells break off and relocate

Cancer Treatment Surgery= remove cancerous cells Cancer Treatment Surgery= remove cancerous cells Radiation= high energy radiation interrupts cell division Chemotherapy= uses drugs to stop cell cycle Last 2 have undesirable side effects

Vocab 9.4 Benign tumor Malignant tumor Cancer Metastasis