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Bio Boarding. Unit 2 Review/ Notes. DNA. Draw a nucleotide. Include: Phosphate, Sugar, and Nitrogen base!. What are the building blocks of DNA and RNA?. Nucleotides!!!. What are the four DNA bases?. A denine T hymine G uanine C ytosine Which bases pair with which?.
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Bio Boarding Unit 2 Review/ Notes
Draw a nucleotide Include: Phosphate, Sugar, and Nitrogen base!
What are the building blocks of DNA and RNA? Nucleotides!!!
What are the four DNA bases? Adenine Thymine Guanine Cytosine Which bases pair with which? What are these base pairings referred to as? Complimentary base pairs
How many Hydrogen Bonds do A&T have between them? C&G? A&T = 2 h-bonds C&G = 3 h-bonds Which bases have stronger Hydrogen bonding between them? C&G!!!
If DNA is a ladder, what are the sides? Alternating Sugar and Phosphate molecules! What are the rungs? Nitrogen bases!
What does the BRCA gene do? Regulate cell cycle (it’s a tumor suppressor gene) What would happen if the BRCA gene was missing? Increased risk for person to get cancer
An example of a carcinogen is cigarette smoke. Why are carcinogens bad for us? Carcinogens are chemicals that cause mutations that lead to cancer
Why do we need mitosis? (why do we need our body cells to divide?) • Growth • Repair damaged cells • Replace old cells
During prophase, what happens so we can see the DNA? DNA coils or condenses into chromosomes
What pulls the sister chromatids apart during anaphase? Spindle fibers! What would happen if one broke during mitosis? DNA wouldn’t be evenly distributed between daughter cells…one would have too much one would have too little
What is the longest phase of the cell cycle? Interphase – where the cell is hanging out and doing its job!
What happens at each checkpoint? G1 checkpoint: Checks for damaged DNA before Synthesis phase (doesn’t want to copy bad DNA!) G2 checkpoint: (after DNA is copied) Prevents mutated DNA from going into mitosis Mitosis checkpoint: Checks spindle fibers from metaphase to anaphase. Makes sure the right amount of DNA gets to each cell!
What is PCR? Polymerase chain reaction and it’s used to make copies of DNA (like a DNA photocopier) Think about why we would need to be able to do this…
What is the purpose of the helicase enzyme? Break H-Bonds to “unzip” the DNA
How would you describe the difference between the DNA in bands A and B? Gene B is the same as A, but there are more copies of the gene in band B making it show up as a thicker and brighter band!
What are the enzymes that perform DNA replication and what are their roles? Helicase – breaks hydrogen bonds between base pairs to unzip DNA DNA Polymerase – adds new nucleotides to a strand of DNA Ligase – reforms sugar & phosphate backbone