Chapter 10 Quest Flashcards
What is cell division?
the process by which a cell divides into two new daughter cells
What are two reasons why cells divide rather than continue to grow indefinitely?
the larger a cell becomes, the more demands the cell places on its DNA
the ore trouble the cell has moving enough nutrients and wastes across the cell membrane
how does cel division solve the problem of increasing size?
each daughter cell gets one complete set of genetic info
What are the two main stages of cell division?
mitosis, cytokinesis
When chromosomes become visible at the beginning of cell division, what does each chromosome consist of?
Chromatids and centromeres
Each pair of chromatids is attached at an area called the
centromere
What is the period of growth in between cell divisions called?
interphase
What is the cell cycle?
the series of events that cells go through as they grow and divide
The division of the cell nucleus during the M phase of the cell cycle is called
mitosis
Interphase is divided into what three phases
prophase
metaphase
anaphase
What happens during the G1 phase?
cell growth
What happens during the S phase?
DNA replication
What happens during the G2 phase?
preparation for mitosis
What are the four phases of mitosis?
prophase
metaphase
anaphase
telophase
What are the two tiny structures located in the cytoplasm near the nuclear envelope at the beginning of prophase?
centrioles, spindle
What is the spindle?
Where the centrioles are located
What is cytokinesis?
the division of the cytoplasm
How does cytokkinesis occur in most animal cells?
the cell membrane is drawn inward until the cytoplasm is pinched into equal parts
What forms midway between the divided nucleus during cytokinesis in plant cells?
cell wall
What happens to the cells at the edges of an injury when a cut in the skin or a break in a bone occurs?
they divide rapidly
What happens to the rapidly dividing cells when the healing process nears completion
slows down
What do cyclins regulate?
the timing of the cell cycle in eukaryotic cells
What are internal regulators
proteins that respond to events inside the cell
What is cancer?
a disorder in which some of the body’s own cells lose the ability to control growth
