Chapter 12 Flashcards
all the DNA in cell
genome
units of information that specify an organisms inherited trait
genes
condensed, packaged DNA found in nucleus
chromosomes
entire complex of DNA and proteins that is building material of chromosomes
chromatin
life of a cell from when it was first formed to its division into 2 daughter cells
cell cycle
what are packaged into chromosomes?
DNA only
what are the 2 types of cells that eukaryotic cells contain?
somatic cells: all cells in body; 2 sets of chromosomes (2n)
gametes: reproductive cells; half as many chromosomes (n)
chromosomes that have replicated but not separated from one another
sister chromatids
where are sister chromatids joined together?
centromere
what are the phases of the cell cycle?
interphase: cell growth and chromosome duplication
mitotic phase: mitosis and cytokinesis
division of genetic material
mitosis
division of cytoplasm
cytokinesis
what are the 5 stages of mitosis?
prophase, prometaphase, metaphase, anaphase, telophase
what are the 2 regulatory proteins involved in cycle control?
cyclin and cyclin dependent kinases
cyclin-cdk complex helping the cell get past checkpoint between G2 and M
maturing promoting factor
abnormal cells that remain at original site
benign tumors
invades surrounding tissue
malignant tumors
when cancer cells spread to other parts of body
metastasis
what are the 3 important checkpoints?
G1, G2, M phases
what does M checkpoint regulate?
makes sure daughter cells have correct amount of chromosomes
what happens during telophase?
chromosomes are at opposite ends of cell, nuclei and nucleolus form
what enzyme is used to cleave sister chromatid?
separase
what happens in anaphase?
sister chromatids separate and move to opposite ends
protein complexes associated with centromeres, each sister chromatin has one
kinetochores
what happens during metaphase?
spindle formation complete, chromatids attach to microtubules at kinetochore, chromosomes lined up at metaphase plate
what happens during prometaphase?
fragments of nuclear envelope form, centromeres attach to kinetochores
what happens in prophase?
chromosomes condense, spindle forms, nucleolus disappears, centrosomes move apart
what are external factors that influence cell division?
growth factors, density dependent inhibition, anchorage dependence
what causes a release by cells to stimulate other cells to divide?
growth factors
what causes crowded cells to stop dividing?
density dependent inhibition
in animal cells, cells must be attached to extracellular matrix of tissue to divide, what is this?
anchorage dependence
