Lessons 4, 5, 6: Cell Cycle, Meiosis, Genetics PDF

**Topic Outline:** - - - - **THE CELL CYCLE** **Cell - the basic unit of life** It has two stages: 1. 2. **INTERPHASE (3 Phases)** - - - **CELL DIVISION (1 Phase)** 1. a. b. c. d. e. 2. **During the Cell Cycle:** - - - - - - **CELL DIVISION**...

**Topic Outline:** - - - - **THE CELL CYCLE** **Cell - the basic unit of life** It has two stages: 1. 2. **INTERPHASE (3 Phases)** - - - **CELL DIVISION (1 Phase)** 1. a. b. c. d. e. 2. **During the Cell Cycle:** - - - - - - **CELL DIVISION** **It functions as:** 1. 2. 3. **Two Types:** - - **This involves:** a. b. **KARYOKINESIS (MITOSIS)** - - - -  **MITOSIS** - - - - **HAPLOID (n) - one set of chromosomes** **DIPLOID (2n) - two sets of chromosomes** - **Facts:** Humans typically have 23 pairs of chromosomes, or **46 chromosomes in total.**  **CHROMOSOME vs CHROMATID** **Chromosomes -** a **DNA molecule** that has all or part of the genetic material of an organism **Chromatid -** one **copy of a newly copied chromosome** +-----------------------------------+-----------------------------------+ | **PHASES OF MITOSIS** | | +===================================+===================================+ | G2 Late Interphase | Cell checks for complete DNA | | | replication. | +-----------------------------------+-----------------------------------+ | Early Prophase | Chromosomes condense and become | | | visible. Spindle fibers | | | *(cytoplasm microtubules)* form | | | as centrosomes move to opposite | | | poles. | +-----------------------------------+-----------------------------------+ | Prometaphase | Nuclear envelope breaks up. | | | Spindle fibers attach to | | | kinetochores on chromosomes | +-----------------------------------+-----------------------------------+ | Metaphase | Chromosomes line up along the | | | equator of the cell. | +-----------------------------------+-----------------------------------+ | Anaphase | Centromeres split as sister | | | chromatids separate and move to | | | opposite poles of the cell making | | | single strand chromosomes. | +-----------------------------------+-----------------------------------+ | Telophase | Nuclear envelope and nucleolus | | | form at each pole. Chromosomes | | | decondense. Spindle disappears. | | | Nucleolus becomes visible. | +-----------------------------------+-----------------------------------+ | Cytokinesis | Division of the cytoplasm into | | | two cells. | | | | | | Animal cell - inward movement | | | | | | Plant cell - cell plate | +-----------------------------------+-----------------------------------+ | G2 Early Interphase | Cells resume normal functions or | | | enter another division cycle. | +-----------------------------------+-----------------------------------+  **CYTOKINESIS** -  **MEIOSIS** - **Two division stages:** A. B. - - - **MEIOSIS (Reduction Division)** A. - - B. - - +-----------------------------------+-----------------------------------+ | **PHASES OF MEIOSIS I** | | +===================================+===================================+ | Interphase | **DNA Replicates.** Cell produces | | | proteins needed for cell | | | division. | +-----------------------------------+-----------------------------------+ | Prophase I (Early) | Chromosomes condense and become | | | visible. | | | | | | (2n = 4) | | | | | | **Synapsis** occurs that pairs up | | | with and binds with a homologous | | | chromosome forming a **tetrad - 4 | | | sister chromatids**. | | | | | | Chromosomes - genetic information | | | **(genes).** | | | | | | **Alleles -** different versions | | | of the same gene on each | | | chromosome. | +-----------------------------------+-----------------------------------+ | Prophase I (Late) | **Crossing over (Recombination)** | | | occurs - chromatids from each | | | homologous chromosome **exchange | | | segments of alleles.** Spindle | | | forms. Nuclear envelope breaks | | | up. | | | | | | Crossing over - gives **genetic | | | variety** in offspring. | +-----------------------------------+-----------------------------------+ | Metaphase I | Paired homologous chromosomes | | | **line up along the equator** of | | | the cell and attached to spindle | | | fibers. | +-----------------------------------+-----------------------------------+ | Anaphase I | Homologous chromosomes **separate | | | to opposite poles of the cell.** | | | Sister chromatids remain joined. | +-----------------------------------+-----------------------------------+ | Telophase I & Cytokinesis | Nuclear envelopes form around | | | chromosomes, which may | | | temporarily decondense. Spindle | | | disappears. **Cytokinesis may | | | divide cells into two.** | +-----------------------------------+-----------------------------------+ | | Ends with **two genetically | | | different haploid daughter | | | cells.** | +-----------------------------------+-----------------------------------+ **PHASES OF MEIOSIS II** ----------------------------------------------- --------------------------------------------------------------------------------------------------------------------------- **DNA does not replicate before Meiosis II.** Prophase II Spindles form. Nuclear envelopes break up. Metaphase II Chromosomes line up along the equator of the cell. Anaphase II Centromeres split as sister chromatids separate to opposite poles of the cell. Telophase II & Cytokinesis Nuclear envelopes assemble around daughter nuclei. Chromosomes decondense. Spindles disappear. Cytokinesis divides cells. **Four nonidentical haploid daughter cells (n = 2).** Each contains only one set of chromosomes. **MEIOSIS** - - - - - **PROPHASE I** - - - - -  **Characteristics** **Mitosis** **Meiosis** ----------------------------------------- ------------------------------------------ -------------------------- **No. of nuclear division** One Two **Type of cell** Somatic cells Sex cells **Type & no. of daughter cells** Two, Diploid Four, Haploid **Genetic variation of daughter cells** Genetically identical Genetically different **Function** Asexual reproduction, repair, and growth Sexual reproduction only **Animal Life Cycle:** - - - **Plant Life Cycle:** - - - - - - -  **TERMS:** a. b. **REPRODUCTIVE CYCLES** A. -  B. - - - - **EXAMPLE:** **FLOWERING PLANTS - angiosperms (sporophyte)** - -  **C. HAPLODIPLONTIC CYCLE** - - - - - **EXAMPLES:** 1. -  2. - - 3. - -  **Called as a FERN THALLUS** **TERMS:** **Non-Vascular Plants** a. **Vascular Plants** a. - - b. - - **PERFECT FLOWER STRUCTURE** - - - - - - - -  **DOUBLE FERTILIZATION** - **FROM FLOWER TO FRUIT** **FROM OVULE TO SEED**  **HUMAN LIFE CYCLE**  **REPRODUCTIVE PATTERNS** - A. B. **ASEXUAL REPRODUCTION** - - - **TYPES OF ASEXUAL REPRODUCTION** I. - - - II. - - - III. - - - IV. - - V. - - **SEXUAL REPRODUCTION** - - - **TYPES OF SEXUAL REPRODUCTION** I. - - - II. - - - - **SEXUAL REPRODUCTION** A. - - B. - - C. - - - **LESSON 4.2 CYCLES AND PATTERNS** **MENDELLIAN AND NON-MENDELLIAN GENETICS** - - - - - - - - - - - - - - - - - - - - - - - -  - - - **3 LAWS OF INHERITANCE BY GREGOR MENDEL** - - - - - - - -  - - - - - - - **2 TYPES OF PUNNETT SQUARES** - - - **NOTE:** Each crossing has **25%** out of its total which is 100%. Always **understand the situation given** before doing the crossing.  **NOTE:** **Genotype Ratio = different letter combinations** **Phenotype Ratio = traits that are visible**  - - - -  **NOTE:** FOIL Method applies by **multiplying the Rr X Yy** and not RrYy X RrYy.  **NON-MENDELIAN TRAITS** - - - - - - - - -  - - - - - - - - - - - - - -  - - - - -  - - - - - - - -  - - - - - - - - - - - -  - - - - - **LESSON 5: POPULATION DYNAMICS** - - **Population is composed of:** - - - - **OTHER IMPORTANT TERMS** **BIOGEOGRAPHY** - - **DEMOGRAPHY** - - **POPULATION SIZE** **NATALITY** - **MORTALITY** - **DENSITY** - - - **DISTRIBUTION PATTERNS** A. - - - B. - - - C. - - -  **FACTORS AFFECTING DISTRIBUTION** **DENSITY DEPENDENT** - - **DENSITY INDEPENDENT** - - **POPULATION SIZE: ENTRANCE AND EXIT** Population Change = (births + immigration) - (deaths + emigration) **POPULATION AGE STRUCTURE** - - - - - **GENERAL AGE STRUCTURE**  **:What is the importance of knowing the human population profile?** We can learn about the factors that influence population growth, the distribution of people across the globe, and the social and economic implications of population change. **What limits population growth?** I. - -  II. - - - III. - -  **OVERSHOOTING CAPACITY** **(Logistic Growth of Sheep)** - - **(Exponential growth of reindeer)** - - -  **SURVIVORSHIP CURVES** - - - **Can be summarized in survivorship curves:** 1. 2. 3. 1. - - - - 2. - - - -  3. - - - - **LESSON 6: CHANGES IN POPULATION OVER TIME** - - - - - - - - - - - - - - - - -  - - - - - - - - **ALLELE FREQUENCY** -  **GENE POOL** - - - **CONTRIBUTING TO THE GENE POOL** - - -  **CALCULATING ALLELE FREQUENCY** - - - - - - - -  **PREDICTING EVOLUTION THROUGH ALLELE FREQUENCY** - -  **ALLELE FREQUENCIES AND EVOLUTION** - - **HARDY-WEINBERG PRINCIPLE** - - **HARDY-WEINBERG ASSUMPTIONS AND EVOLUTION** - - - - - - - **HARDY-WEINBERG EQUATION** - - - - - - - - -  **SAMPLE PROBLEMS FOR HARDY-WEINBERG EQUATION** 1. - - - - - - - 2. - - - - - - - 3. - - - - - - - - -  **MECHANISMS OF EVOLUTION: FORCES THAT CHANGE GENE FREQUENCIES IN POPULATIONS** **MUTATION** - - - -  **NON-RANDOM MATING** - - - - - -  **GENETIC DRIFT** - - - - - - - - - - -  - - - - - -  **MIGRATION** - - - - - **NATURAL SELECTION** - - - - - - - -