Cell Reproduction Cell Cycle Mitosis Meiosis

Cell Cycle Interphase – the phase of a cell cycle in which a cell grows to mature size and carries out typical activities –G1: Growth stage, cell performs typical activities and grows to a mature size –S: Synthesis stage, makes a copy of DNA –G2: Growth twice, cell makes copies of the organelles and doubles in size

Mitosis The process of dividing a cell’s nucleus to make to identical nuclei –Prophase: chromosomes in the DNA have been copied –Metaphase: nucleus disappears and paired chromosomes line up in the center of cell –Anaphase: pairs of chromosomes separate and move to opposite sides of the cell –Telophase: two nuclei form and the cell divides into two identical daughter cells Cytokinesis – division of the cytoplasm

Cancer Cancer is a physical condition in which a cell grows without control, dividing too much Tumor – a ball of cancerous cells –Benign tumor: grow in only one area of the body –Malignant tumor: spreads throughout the body Metastasis – process of cancer cells spreading to other body areas

Cancer

Meiosis Gametes, sex cells, perform the process of meiosis, which is the division of sex cells Male gametes are call sperm cells and female gametes are call egg cells. Gametes are referred to as haploid cells; one copy of each kind of chromosome Somatic cells, all other kinds of cells, are referred to as diploid cells; two copies of each kind of chromosome

Meiosis I Tetrad – a pair of homologous chromosomes joined together Prophase I: The chromosomes in DNA have been copied. Chromosomes are paired Metaphase I: Paired chromosomes line up Anaphase I: Paired chromosomes separate and move to opposite sides of the cell Telophase I: The cell divides, resulting in two cells with two copies of the same chromosome

Meiosis I Prophase IMetaphase I Anaphase I Telophase I

Meiosis I Crossing over – the process of homologous chromosomes in a tetrad trading pieces of similar DNA –Makes every organism unique –Creates different chromosomes that are passed to offspring –Ex. Parents with blue eyes have children with green eyes

Meiosis II Prophase II: Paired chromosomes line up in each haploid daughter cell Metaphase II: Members of each pair line up in the middle of the cell Anaphase II: Members of each pair move to opposite sides of the cell Telophase II: The cells divide, resulting in four haploid daughter cells with one copy of each type of chromosome

Meiosis II Prophase II Metaphase II and Anaphase II Telophase II

Male Reproductive System Testis – the male sex organ that produces sperm cells Scrotum – the sac that holds the testes Penis – the male organ that delivers the sperm to the female body Prostate gland – the structure that mixes and stores semen that is ready to be ejaculated

Male Reproductive System Vas deferens – the tubes that connect the testes to the urethra Seminiferous tubules – the tissue in the testes where sperm are produced Urethra – the tube that carries urine and semen out of the body Testosterone – the male sex hormone Spermatogenesis – the process of making sperm cells

Male Reproductive System Penis Urethra Scrotum Testis Seminiferous tubules Vas deferens Prostate gland Urinary bladder

Female Reproductive System Ovary – the female organ that makes egg cells (oocyte) Follicle – a ball of cells with a growing egg cell found inside Fallopian tube – a tube through which eggs pass from an ovary to the uterus Uterus – an organ in most female mammals that holds and protects an embryo

Female Reproductive System Vagina – tube-like canal in the female body through which sperm enter Cervix – an opening that connects a female’s uterus and vagina Oogenesis – the process of creating an egg cell Estrogen – the female sex hormone

Female Reproductive System

Conception and Pregnancy Fertilization – sperm cell joins with an egg cell in the Fallopian tube Conception – the joining of the sperm and egg Pregnancy – the development of a fertilized egg into a baby inside the female’s body Gestation time – the period of development of a mammal from fertilization until birth

Conception and Pregnancy Zygote – fertilized egg that has undergone mitosis Embryo – a fertilized egg up until week nine of gestation Fetus – has all of the major structures found in babies Umbilical cord – contains blood vessels that provide the embryo with food and oxygen Placenta – tissue that connects the baby to the mother’s food and oxygen supply