1/13 Daily Catalyst Pg. 67 Gene Regulation 1. How many chromosomes are found in a human somatic cell? 2. How many chromatids are in a duplicated chromosome? 3. What stage of mitosis is shown below? How do you know?
1/13 Daily Catalyst Pg. 67 Gene Regulation 1. How many chromosomes are found in a human somatic cell? 46 (23 from mom and 23 from dad) 2. How many chromatids are in a duplicated chromosome? Two 3. What stage of mitosis is shown below? How do you know? Anaphase, chromatids are pulled APART
1/13 Class Business Pg. 66 Gene Regulation Quiz #16 on Friday Tutoring after school, during 4th period, and during lunch Schedule tutoring sessions with me Parent Night 1/13 (TONIGHT) Extra Credit for attending 4-6 pm in the Cafeteria
Study Assignment New studying assignment Date Time Notes You are required to study a certain amount of hours per week independently AND with a group/partner per month Independently= 6 hours per week Group/partner= 4 hours per month Sheet is due at the end of each month on the last Friday (Jan. 30th) Name(s) Date Time Topic(s) Covered Notes Signature
Review the stages of Mitosis and discuss methods of cell regulation. 1/13 Objective Review the stages of Mitosis and discuss methods of cell regulation.
Mitosis Review
Pg 66. Binary Fission What type of cells undergo mitosis? Eukaryotic- plants and animal cells What about bacteria? Key Point #1: Prokaryotes reproduce by binary fission Meaning “division in half”
Pg. 66 Binary Fission Bacterial DNA is circular in shape Bacterial DNA must be replicated before cell division Replication begins at the Origin of Replication A specific site on the chromosome The origins move to opposite end of the cell The cell begins to elongate The plasma membrane grows inward and forms two new cells
Pg. 67 Gene Regulation The cell cycle so it is a cycle! It continues to go around and around.
Cell Cycle regulation There is evidence towards cytoplasmic signals that control the cell cycle. Key Point #1: Cell cycle control: a set of molecules in the cell that both trigger and coordinates the CC. Regulated at certain checkpoints (Like a dishwashing machine)
Cell Cycle regulation Key Point #2: Checkpoint: a control point where stop and go signals exist Checkpoints register signals form inside and outside the cell if the cell cycle should proceed OR STOP 3 checkpoints: G1, G2, and M phase
Cell Cycle regulation G1 check point: AKA the “restriction point” Most important checkpoint GO(green light): complete G1, S, G2, and M phases STOP: Exit the cycle and switch into a non dividing state (G0) Most cells are in the G0 phase Mature nerve cells do no need to divide
Cyclin-dependent Kinases (Cdks): Activate or inactivate other proteins Cell Cycle regulation Cyclin-dependent Kinases (Cdks): Activate or inactivate other proteins Checkpoint at G1 and G2 Cyclin: cyclically fluctuating concentration Kinase: activate or inactivate proteins by giving them a phosphate group
MPF MPF: maturation-promoting factor M-phase promoting factor Triggers the cell’s passage past the G2 checkpoint into M phase When cyclin is high during G2, this causes MPF to phosphorylates other proteins. During anaphase, MPF switches itself off
PDGF Made by platelets PDGF binds to a receptor and this triggers G1 checkpoint and get ready to divide IN HEALING!
Cancer Cancel cells do not heed the normal signals that regulate the cell cycle. They divide excessively and invade other tissues. If unchecked, they can kill organisms.
Cancer Cancer cells do not stop dividing when growth factors are depleted. Cancer cells may make their own growth factors!
Process of a cancerous cell Transformation: a normal cell converts into a cancer cell Immune system will cell the transformed cell, if not, the cell will rapidly divide and form a tumor Benign tumor: not dangerous tumor Malignant tumor: invasive and starts to impair normal function (cancer) Cancer cells metastasize: spread from original location
Mitosis Review Label each picture of mitosis:
Cell regulation Review What protein (regulator) acts at G1? Cdk’s. MPF regulates after G2 phase and before M-phase.