Chapter 10 Flashcards
What is the difference between chromatin and chromosomes?
Chromatin: Lunchroom
Chromosomes: Seating Chart
How do living things grow?
By producing more cells.
What happens when the cell becomes larger?
To much demand on the DNA.
The cell has more trouble moving enough nutrients and wastes across the cell membrane.
DNA does not get bigger, so what happens?
It gets to big to send a receive information in a timely manner.
Define Surface Area
The area showing on an object.
What increases faster; Cell volume or surface area?
Cell volume.
Right before a cell gets too large it divides into what?
Two daughter cells.
This is called cell division.
Define Mitosis
Division of the cell nucleus.
Cytokinesis
Division of cytoplasm.
Form of asexual reproduction.
What are chromosomes made f?
DNA
When is the only time chromosomes are visible?
During cell division.
What is the centromere for?
Acts as a rope or halter.
List and describe the 4 phases of cell division.
M: Mitosis and cytokinesis.
G¹: Growth and activity.
S: Synthesis or replication
G²: Growth and activity.
Interphase
Normal cell growth before division.
During G¹ the cell increases in size and makes proteins and organelles.
During S phase chromosomes replicate and synthesis of DNA takes place.
During the shortest phase, G², the organelles, and molecules needed for cell division are produced.
During G¹ the cell increases in size and makes proteins and organelles.
During S phase chromosomes replicate and synthesis of DNA takes place.
During the shortest phase, G², the organelles, and molecules needed for cell division are produced.
List and describe the 4 phases of mitosis.
Prophase: Chromosomes become visible.
Metaphase: Chromosomes line up in the middle.
Anaphase: Chromosomes separate and sets are pulled towards poles.
Telophase: Chromosomes disperse into chromatin.
The nucleolus disappears and the nuclear envelope breaks down.
The nucleolus disappears and the nuclear envelope breaks down during prophase.
Cytokinesis
Usually, cell membrane pinches inward until two cells are made.
Separate cytoplasm.
What happens when certain cells come in contact?
When cells come in contact with other cells, they respond by not growing.
What is cyclin?
a protein that would cause a spindle to form (start mitosis).
Regulates the timing of cells.
How many cells also regulate timing?
Dozens
What are internal regulators?
Internal regulators are proteins that respond to events inside the cell.
What are external regulators?
External regulators are proteins that respond to events outside the cell.
What is cancer?
Disorder in which cells lose the ability to control growth.
Mitosis gone wild.
What are tumors?
Masses of cells.
Causes of cancer?
Many causes from tobacco, radiation, viruses, etc.
Many have a defect in p53 genes which normally halts cell cycle.
Many have a defect in p53 genes which normally halts cell cycle.
