Flashcards in Cell Reproduction Quiz Deck (35):
How long do cells live for?
Until they die or split
How often do cells divide?
Varies with each organism
What are some cells that rarely divide?
Muscles, liver, nerves, brain cells
What is it called when cells divide too much?
Why does unicellular life divide?
What makes big cells inefficient?
Too much volume too little surface area
How is cell efficiency determined?
By its surface area to volume ratio
Why does multicellular life divide?
To grow and heal
What part of a cell actually divides during mitosis?
DNA actually divides
What is another name for mitosis
What happens to a cell during prophase?
The DNA condenses, organizes and the chromosomes structure appears
Why do chromosomes become visible during prophase?
Because DNA condenses
What is the cell cycle?
An ordered series of events in the life of a eukaryotic cell
The stage during which cell carries out its metabolic processes and performs it's functions
What is the order of the phases
During G1 what is the cell doing?
What is being duplicated during S phase?
The genetic material (DNA & chromosomes)
What happens on the g2 phase?
The cell prepares for division by making copies of its organelles such as mitochondria and chloroplasts
What happens during the mitotic phase
What happens during cytokinesis
Examples of when something is in G1 but eventually stop growing
Nerve & heart cells
What must DNA be passed to?
When is DNA copied
When do chromosomes form?
During g2 because nda spools around histones (exceptionally emall proteins)
Describe how chromosomes form
1. Chromosomes duplicate
2. Creates sister chromatids
3. Identical chromosomes separate and ate distributed to two daughter cells
What happens in prophase?
Chromosomes finish forming sister chromatids. Spindle fibers form
What are spindle fibers?
Made of microtubules
What do spindle fibers do?
Stretch from pole to pole & eventually connect the centromere of the chromosome
What 2 cell parts break down during prophase?
Nuclear envelope and nucleolus
Where are microtubules arranged in a ring formed?
What is the function of microtubules
Helps form cytoskeleton & spindle fibers
What happens during g2
Asters form and centrioles replicate
Short microtubules in patter around the centriole
Acts as a substitute cytoskeleton only in animal cells
What happens in metaphase
Spindle fibers move chromosomes to the equator