Cell Cycle Flashcards
What 3 things do cells divide for?
To grow heal or reproduce an organism
Sex cells
Cells used for reproduction
How many sets of chromosomes do sex cells have?
1 set of chromosomes (23)
Can be referred to as haploid cells
Somatic cells
Any cells not used for reproduction
How many sets of chromosomes do somatic cells have?
2 sets of chromosomes (46)
Can be referred to as diploid cells
Mitosis
Process of nuclear replication
4 steps of mitosis
Prophase
Metaphase
Anaphase
Telophase
Prophase
-Preparation stage for nuclear division
-Chromosomes condense out of nucleoplasm
-centrioles move to opposite ends and act as attachment site for spindle fibres
Chromatids
Strands of DNA and attached protein
Centromere
Point where chromatids join
What stage does the nuclear membrane dissolve?
Prophase
Centrioles are only found in animal cells true or false?
True
Metaphase
Second stage of mitosis
Chromatids prepare to be separated and divided
Gather at the centre line of the cell (equatorial plane)
Anaphase
Third stage of mitosis where genetic information is divided and sorted to opposite end of cell
Centromeres detach resulting in separated chromosome pairs
What do centrioles work with spindle fibres to do?
Make sure each end of cell receives equal number of chromosomes as well as one of each chromosome
Telophase
Final step of nuclear division where new nuclei are formed in prep for cell division
When do nuclear membranes start to form around chromosomes?
Telophase
Cytokinesis
Movement of cytoplasm and organelles
Contractile rings
Causes cell membrane to contract and narrow at centre of cell
What happens when the contractile ring closes?
Pinches at the centre resulting in 2 daughter cells
The 3 stages of interphase
First growth stage
Synthesis stage
Second growth stage
First growth stage
Cell grows and performs it’s normal functions
Longest stage
S stage (synthesis)
Cells first prep for mitosis and cell division
Amount of DNA doubles
Second growth stage
Cell grows until it is large enough for cell division
A lot of protein synthesis in this stage
What is located at the end of each growth stage in interphase?
Checkpoint
G1 checkpoint proteins
Ensure cells have sufficient size and amount of nutrients
In order to exit G1 checkpoint protein cell must recieve what?
Signal from outside of cell
G2 checkpoint protein
Ensure cell doesn’t enter M phase until DNA damage inspection is complete
Cells that follow a diploid cell cycle
Somatic cells
What are sex cells also called?
Gametes
How are sex cells produced?
Meiosis
Difference between meiosis and mitosis
Meiosis contains a second nuclear division
Prior to second cell division in meiosis what process happens?
Genetic recombination
Genetic recombination
Process where sister chromosomes exchange DNA to increase genetic variation
Tumours
Cells that grow at a uncontrolled rate
Benign tumors
Tumors that are localized
Malignant tumors
Tumors that invade surrounding tissue or spread throughout body
Also known as tumors
Metastasis
Spread of malignant cells throughout body resulting in tumors
How is all cancer caused?
Genetic changes to a cell
Genetic changes change cell cycle resulting in too much cell division
Oncogene
Gene that has potential to make cell cancerous
What 4 factors can trigger an oncogene?
Mutation during DNA replication
Mutation due to a carcinogen
Mutation or damage due to radiation
DNA inserted by a virus (HPV)
