Unit 4: The Nucleus Test- Part 1
College Prep Review
THE STRUCTURE OF THE GENETIC MATERIAL
1.
Explain the Unity in Diversity theme.
All life has DNA but the sequence of bases is what makes all things different
2.
Explain how each of the following scientists contributed to our knowledge of the genetic material.
a) Meischer _Discovered DNA
b) Wilkens / Franklin took pictures of DNA using X-Ray crystalography
c) Watson / Crick Built the first model of DNA determining it’s structure
3.
NOTE: Also review scientists from previous units: Leeuwenhoek, Hooke, Singer/Nicholson,
Schleiden, Schwann, Virchow.
4.
Where is the "code" in the DNA?
SUGAR / PHOPHATES / BACKBONE / BASES
5.
Bases that fit together based on shape are called pyrimidines and purines
6.
What two molecules make up the DNA backbone? Sugars and phosphates
7.
Draw the ladder structure of DNA and label: base, sugar, phosphate, nucleotide.
THE FUNCTION OF THE GENETIC MATERIAL
8.
What are the 2 general functions of DNA?
Control the cell
Make mRNA=> proteins
9.
DNA controls the cell by giving the directions to make proteins
10. There are ~20,000 genes on the 46 human chromosomes.
11.
How are genes and proteins related? one gene codes for the making of one protein
12. What are the building blocks of proteins? Amino acids
13. Codons and anticodons are the same because they both consist of nitrogen bases (nucleotides)
14. A codon is part of a mRNA molecule while an anticodon is part of a tRNA molecule.
15. List THREE differences between DNA structure vs. RNA structure.
1 DNA is large, RNA is small
2. DNA is double stranded, RNA is single
3. DNA has thymine, RNA has uracil
4. DNA is helical, RNA is not
5. DNA has 1 type, RNA has 3 mRNA tRNA rRNA
16. What type of macromolecule are DNA and RNA? Nucleic acid
17. List and describe the three types of RNA.
1. mRNA carries the gene’s message from DNA to ribosome
2. tRNA brings amino acids to the ribosome
3. rRNA makes up the structure of the ribosome
18. List the steps of transcription in detail.
1. Helicase unzips DNA at the gene
2. RNA Polymerase adds nucleotides to a strand of mRNA
3. mRNA detaches and leaves the nucleus to the cytoplasm
19. Where in the cell does transcription occur? nucleus
20. List the steps of translation in detail.
1. Ribosome attaches to the mRNA at the start codon (AUG)
2. tRNA brings in an amino acid by matching its anitcodon to the codon on mRNA
3. Amino acids of 2 tRNA molecules are bonded together
4. When the ribosome reads a stop codon, the polypeptide chain (protein) is released
21. Where does translation occur? Cytoplasm (ribosome)
22. What type of molecules are DNA polymerase, RNA polymerase, helicase? enzymes
23. Describe how to use the codon chart to determine the order of amino acids in a protein.
Start at the left, then read the top, then read the right
THE CELL CYCLE
24. The collection of stages in a cell’s life is called the Cell Cycle
25. List the two basic steps of DNA replication.
1. Helicase unzips the DNA (at many spots)
2. DNA polymerase adds nucleotides to BOTH sides of the DNA strand
26. What does semi-conservative refer to? One strand is old and one is new; “saves half”
27. What is the result of DNA replication and why is it important?
2 identical strands of DNA; this is important because each new cll needs to be the same.
28. State the chromosome theory of heredity.
Genes are located on chromosomes and these are passed down from one generation to the next
29. How are chromosomes, genes and DNA related? Chromosomes are made up of DNA, and genes are
sections of the DNA (on the chromosomes)
List the 2 main parts of cell cycle:
Interphase and Mitosis (with cytokinesis being a third)
30. Describe the stages of the cell cycle (be sure to know the stages & what happens in each stage)
1- Interphase
a. G1- growth and organelle reproduction, S- DNA Replication, G2- growth for division
2- Mitosis- splits the nucleus
a. PMAT
31. Cancer can be generally described as uncontrolled cell growth
32. What is a tumor? Abnormal large clump of cells
33. How are the cell cycle, enzymes and DNA connected? The cell cycle is controlled by enzymes
because the checkpoints use enzymes to make sure the cell cycle is working properly. DNA
replication is also contolled by enzymes suh as helicases and polymerases.
34. List the 3 main parts of cell cycle:
Interphase and Mitosis (with cytokinesis being a third)
35. What 2 events happen during interphase?
Growth and DNA replication (if division is necessary
EFFECTS OF MUTATIONS IN THE GENETIC MATERIAL
21. A mutation is a mistake is the genetic code of a cell
22. 2 basic types of mutations: point mutation and frameshift mutation
23. What is the difference between an inherited and an acquired mutation? Inherited traits are those
you are born with and acquired traits you pick up.
24. Describe how environmental agents can cause mutations. Carcinogens can change the DNA
sequences of cells
28. What is the difference between a point DNA mutation and a frameshift DNA mutation?
Point changes just one base (one “point”)
Framshift takes one out or adds one, changine all codons after it.
25. If a DNA mutation occurs in body cells it can lead to Cancer
26. If a DNA mutation occurs in sex cells the result is genetic disorder
27. What is sickle cell anemia? Mutation in the gene that makes hemaglobin
28. What is the basic cause of sickle cell anemia? Mutation in a gene
29. Nondisjunction is when homologous chromosomes don’t separate properly in anaphase I