Cell Reproduction Chromosomes made of DNA DNA stores

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Cell Reproduction

Cell Reproduction

Chromosomes: made of DNA

Chromosomes: made of DNA

DNA: stores all genetic information -genes: a hereditary unit of DNA -4 bases: -Adenine

DNA: stores all genetic information -genes: a hereditary unit of DNA -4 bases: -Adenine -Thymine -Guanine -cytosine

DNA in the Cell 1. 2. 3. 4. 5. Chromosome Supercoil Subcoil One coil

DNA in the Cell 1. 2. 3. 4. 5. Chromosome Supercoil Subcoil One coil DNA with histine protein 6. DNA

Chromosome Anatomy

Chromosome Anatomy

Chromosome Types 1. Sex Chromosomes: determines the sex of an organism -XY: male -XX:

Chromosome Types 1. Sex Chromosomes: determines the sex of an organism -XY: male -XX: female 2. Autosomes: All other chromosomes of an organism

Chromosome Duplication

Chromosome Duplication

Homologous Chromosomes: two copies of each autosome – same size, shape, and genes

Homologous Chromosomes: two copies of each autosome – same size, shape, and genes

Karyotype: photomicrograph of chromosomes Humans have 22 pairs of autosomes and 1 pair of

Karyotype: photomicrograph of chromosomes Humans have 22 pairs of autosomes and 1 pair of sex chromosomes

Diploid Cells (2 n): cells with both sets of chromosomes (both homologous pairs) 46

Diploid Cells (2 n): cells with both sets of chromosomes (both homologous pairs) 46 chromosomes/23 pairs in humans

Haploid cells (1 n): cells with one set of chromosomes

Haploid cells (1 n): cells with one set of chromosomes

“C” words of Cytology 1. Chromosome: condensed genetic material 2. Chromatid: one of two

“C” words of Cytology 1. Chromosome: condensed genetic material 2. Chromatid: one of two identical copies of DNA 3. Centromere: region that joins the chromatids

“C” words of Cytology 4. Centrioles: cylindrical structures that assist in cell division 5.

“C” words of Cytology 4. Centrioles: cylindrical structures that assist in cell division 5. Centrosome: dark regions in the cytoplasm that create spindle fibers

Cell Division: all cells come from preexisting cells

Cell Division: all cells come from preexisting cells

2 Types of Division

2 Types of Division

1. Mitosis: cell division which produces 2 diploid, identical cells

1. Mitosis: cell division which produces 2 diploid, identical cells

2. Meiosis: cell division which produces 4 haploid cells

2. Meiosis: cell division which produces 4 haploid cells

Cell Life Cycle 1. Interphase: G 1, S, and G 2 G = growth

Cell Life Cycle 1. Interphase: G 1, S, and G 2 G = growth S = Synthesis 2. M phase: mitosis – nuclear division 3. Cytokinesis: cytoplasm division

Interphase 1. Interphase: DNA not visible -nucleus still intact

Interphase 1. Interphase: DNA not visible -nucleus still intact

Phases of Mitosis 2. Prophase: chromosomes become visible -nucleus disintegrates

Phases of Mitosis 2. Prophase: chromosomes become visible -nucleus disintegrates

Phases of Mitosis 3. Metaphase: chromosomes connect at the centromere to spindle fibers -line

Phases of Mitosis 3. Metaphase: chromosomes connect at the centromere to spindle fibers -line up at the equatorial plate

Phases of Mitosis 4. Anaphase: spindle fibers recede -pull chromosomes apart -chromosomes retreat to

Phases of Mitosis 4. Anaphase: spindle fibers recede -pull chromosomes apart -chromosomes retreat to opposite ends

Phases of Mitosis 5. Telophase: nucleus reforms Cytokinesis splitting the cell -2 daughter cells

Phases of Mitosis 5. Telophase: nucleus reforms Cytokinesis splitting the cell -2 daughter cells are formed

Meiosis: cell division which produces 4 haploid cells

Meiosis: cell division which produces 4 haploid cells

Haploid: a cell with half the number of chromosomes (1 n)

Haploid: a cell with half the number of chromosomes (1 n)

Fertilization: the fusion of two gametes (sperm/eggs)

Fertilization: the fusion of two gametes (sperm/eggs)

Review terms:

Review terms:

Karyotype

Karyotype

Homologous Chromosomes: identical chromosomes – one from each parent

Homologous Chromosomes: identical chromosomes – one from each parent

Chromatid: one of two identical copies of the same DNA

Chromatid: one of two identical copies of the same DNA

Mitosis vs. Meiosis Mitosis Meiosis -Produces two offspring cells of 2 n -One cell

Mitosis vs. Meiosis Mitosis Meiosis -Produces two offspring cells of 2 n -One cell division cycle -produces body cells -no chromosomes cross over -produces four offspring cells of 1 n -two cell division cycles (meiosis I & 2) -produces gametes -chromosomes cross over

8 Stages of Meiosis Prophase I Metaphase I Anaphase I Telophase I Meiosis I

8 Stages of Meiosis Prophase I Metaphase I Anaphase I Telophase I Meiosis I Prophase II Metaphase II Anaphase II Telophase II Meiosis II

Prophase I -Chromatids form -Homologous chromatids pair up to form tetrads

Prophase I -Chromatids form -Homologous chromatids pair up to form tetrads

Metaphase I -tetrads line up at equatorial plate -Crossing over: breaking off of arms

Metaphase I -tetrads line up at equatorial plate -Crossing over: breaking off of arms of chromatids and switching places on another homologous chromosome

Anaphase I -tetrads are pulled apart

Anaphase I -tetrads are pulled apart

Telophase I -cytokinesis occurs

Telophase I -cytokinesis occurs

Prophase II

Prophase II

Metphase II

Metphase II

Anaphase II

Anaphase II

Telophase II

Telophase II

Spermatogenesis: meiosis that produces sperm Produces 4 fertile cells; in humans @ 400 billion

Spermatogenesis: meiosis that produces sperm Produces 4 fertile cells; in humans @ 400 billion

Oogenesis: meiosis that produces egg cells Produces 1 fertile cell; about 400 in a

Oogenesis: meiosis that produces egg cells Produces 1 fertile cell; about 400 in a lifetime

Types of Reproduction 1. Sexual reproduction: offspring are the result of combination of parental

Types of Reproduction 1. Sexual reproduction: offspring are the result of combination of parental genetics 2. Asexual reproduction: no exchange of genetic information – genetically identical to parent

Nature protects the female

Nature protects the female

Cellular Disorders

Cellular Disorders

Cancer: a mitotic disorder

Cancer: a mitotic disorder

Characteristics: 1. 2. 3. 4. Abnormal rates of cell division; uncontrolled Produces malfunctioning cells

Characteristics: 1. 2. 3. 4. Abnormal rates of cell division; uncontrolled Produces malfunctioning cells Kills the organism Lack Density Dependent Inhibition (DDI)

Density Dependent Inhibition (DDI) Ability of a cell to “sense” space – ability to

Density Dependent Inhibition (DDI) Ability of a cell to “sense” space – ability to stop growth in a restricted space

Density Dependent Inhibition (DDI) Lack of DDI – cells continue to divide – causes

Density Dependent Inhibition (DDI) Lack of DDI – cells continue to divide – causes tumors

Types of Tumors 1. Benign: cancer cells remain at the original site 2. Malignant:

Types of Tumors 1. Benign: cancer cells remain at the original site 2. Malignant: cancer cells become aggressive and spread throughout the body

Metastasis: movement of cancer through the blood/lymph to other organs

Metastasis: movement of cancer through the blood/lymph to other organs

Causes: carcinogens and contributing factors

Causes: carcinogens and contributing factors

-smoking

-smoking

-radiation

-radiation

-virus (HPV)

-virus (HPV)

-genetic makeup

-genetic makeup

Treatments

Treatments

-surgical removal

-surgical removal

-radiation treatment

-radiation treatment

-chemotherapy: taxol, vincristine, vinblastine

-chemotherapy: taxol, vincristine, vinblastine

Cellular Differentiation -begins following fertilization -process by which generic cells gain specific functions -mitosis

Cellular Differentiation -begins following fertilization -process by which generic cells gain specific functions -mitosis process

Stem Cells: undifferentiated cells that can become any type of cell Bone Cell Neuron

Stem Cells: undifferentiated cells that can become any type of cell Bone Cell Neuron (nerves) Muscle Cells Skin Cells Cardiac Muscle Stem Cells