Chapter 19 Flashcards
Is diffuse, loosely arranged form of DNA and proteins (histones)
Chromatin
Found in both males and females
Autosomes
Contain genes that control gender
Sex Chromosomes
Females
XX
Males
XY
Segments of chromosomes that contain the code for one or more proteins
Genes
Series of changes a cell goes through from the time it is formed until it reproduces itself
Cell Cycle
Makes up most of cell’s “life”
Interphase
Lots of cell growth; organelles doubled
G1 Phase
Cell’s DNA is duplicated; each chromosome consists of two sister chromatids
S Phase
Continued cell growth; proteins needed for division made
G2 Phase
Non-growing, non-dividing state
G0 Phase
Usually involves division of nucleus (mitosis) and division of cytoplasm (cytokinesis)
Cell Division
Involves separation of sister chromatids of duplicated chromosomes
Mitosis
Chromatin condenses to form chromosomes (duplicated); nuclear envelope dissolves; mitotic spindle begins to form
Prophase
Spindle fibers attach to centromeres; chromosomes randomly arranged
Prometaphase
Spindle fully formed; duplicated chromosomes attached to spindle fibers align at center of cell (metaphase plate)
Metaphase
Mitotic spindle pulls sister chromatids of duplicated chromosomes apart; chromatids move toward opposite ends of cell
Anaphase
Sister chromatids arrive at opposite ends of cell and become chromatin; mitotic spindle breaks down and nuclear envelopes form
Telophase
One parent cell divides to form two daughter cells
Cell Division
Four daughter cells formed from one parent cell
Meiosis
…. consists of prophase 1, metaphase 1, anaphase 1, and telophase 1
Meiosis
Pair up and swap genes
Homologous Chromosomes
Changes in chromosome number
Chromosome Inheritance
Resulting in trisomy or monosomy
Nondisjunction
Include deletion, duplication, inversion, and translocation
Changes in chromosome structure
