Unit 5: Heredity

• Genome: The genetic material of an organism or virus
• Chromosomes: structures made of one DNA molecule and proteins
• Somatic Cells: body cells
• Gametes: reproductive cells
• Chromatin: The complex of DNA and proteins that makes up eukaryotic chromosomes.
• Centromere: Point on a chromosome by which it is attached to a spindle fiber during cell division.
• Sister Chromatids: Identical copies of a chromosome; full sets of these are created during the S subphase of interphase.
• Cytokinesis: division of the cytoplasm to form two separate daughter cells(immediately after mitosis, meiosis I, or meiosis II.)
• Meiosis: Cell division producing haploid gametes
• Mitotic (M) Phase: mitosis and cytokinesis

  Mitosis: Cell separates and divides chromosomes

  Cytokines: Cell divides cytoplasm and organelles.
• Interphase: Cell grows, replicates chromosomes, produces new organelles and cyclins.
• G1 phase: Cell grows, duplicates organelles, and gathers materials for DNA replication.
• S phase: DNA replication occurs
• G2 Phase: growth and final preparation for division, nucleus well defined.
• Kinetochore: A structure within the centromere containing the motor protein dynein. Moves the chromosomes apart during anaphase.
• Cell Cycle Control System: A cyclically operating set of molecules in the eukaryotic cell that both triggers and coordinates key events in the cell cycle.
• Cyclin: a protein that regulates the cell cycle
• CDK: A protein kinase that is active only when attached to a particular cyclin. Activity rises and falls depending on the concentration of the cyclin partner.
• growth factors: Regulatory proteins, ensure that cell division occurs properly
• Density Dependent Inhibition: crowded cells stop dividing
• Prophase: Chromosomes become visible, nuclear envelope dissolves, spindle forms
• Telophase: The chromosomes begin to stretch out and lose their rodlike appearence. A new nuclear membrane forms around each region of chromosomes.
• Cytokinesis in plants cell: plate forms
• Cytokinesis in animals: Cleavage furrow forms
• Binary Fission: one cell divides to form two identical cells
• Karyotype: A display of the chromosome pairs of a cell arranged by size and shape.
• Sex Chromosomes: X and Y chromosomes.
• Autosomes: non-sex chromosomes
• Diploid: 2 sets of chromosomes
• Haploid: having a single set of unpaired chromosomes
• Fertilization: Fusion of an egg and sperm cell
• Zygote: diploid fertilized egg
• Tetrad: structure containing 4 chromatids that forms when homologs pair during meiosis
• Hybridization: The cross of two true-breeding parents. (BB x bb)
• F1 generation: offspring of the P generation
• F2 generation: offspring of the F1 generation
• Alleles: Different forms of a gene
• Punnet Square: A chart that shows all the possible combinations of alleles that can result from a genetic cross
• Homozygous: having two identical alleles for a trait. BB or bb
• Heterozygous: having two different alleles for a trait. Bb