Question

genetic code study guide

1. what are the 4 nitrogenous bases for dna?
2. what are the 4 nitrogenous bases for rna?
3. compare and contrast the structural differences of dna and rna.
4. what does semiconservative mean?
5. what would a semiconservative dna structure look like?
6. what kinds of bonds are holding the nitrogenous bases together?
7. what is chargaffs rule for dna and rna?
8. what is the process of synthesis, modification, and transportation of proteins?
9. what are the different enzymes involved in protein synthesis? what are their functions?
10. what are the functions of the different types of rna?
11. what occurs during translation?
12. what happens during transcription?
13. list and describe the different mutations.
14. what is the relationship between the nucleus and the ribosomes?
15. what would be an example of a dna sequence that is identical during replication and transcription?
16. where can mutation errors occur?
17. how are disorders expressed in humans?
18. what would be affected if a dna molecule did not properly replicate?
19. what would happen if all the enzymes involved in dna replication stopped working properly?
20. what does the process of gene regulation impact?
21. what kind of mutation causes sickle - cell anemia and how is it expressed in humans?

Explanation:

1. The four nitrogenous bases for DNA are adenine (A), thymine (T), guanine (G), and cytosine (C).
2. The four nitrogenous bases for RNA are adenine (A), uracil (U), guanine (G), and cytosine (C).
3. DNA is double - stranded and has deoxyribose sugar, while RNA is usually single - stranded and has ribose sugar.
4. Semiconservative means that during DNA replication, each new DNA molecule consists of one old strand and one new strand.
5. A semiconservative DNA structure would have one parental strand and one newly synthesized strand in each of the two daughter DNA molecules.
6. Hydrogen bonds hold the nitrogenous bases together.
7. Chargaff's Rule for DNA states that the amount of adenine equals thymine and the amount of guanine equals cytosine. RNA is single - stranded and doesn't strictly follow this rule in the same way.
8. The process of synthesis, modification, and transportation of proteins involves transcription (DNA to RNA), translation (RNA to protein), and post - translational modifications.
9. Enzymes in protein synthesis include RNA polymerase (transcribes DNA to RNA), aminoacyl - tRNA synthetase (attaches amino acids to tRNA), and peptidyl transferase (forms peptide bonds).
10. mRNA (messenger RNA) carries the genetic code for protein synthesis, tRNA (transfer RNA) brings amino acids to the ribosome, and rRNA (ribosomal RNA) is part of the ribosome structure.
11. During translation, the mRNA sequence is read by the ribosome, and tRNA brings the appropriate amino acids to form a polypeptide chain.
12. During transcription, an RNA molecule is synthesized from a DNA template by RNA polymerase.
13. Mutations include point mutations (substitution of a single base), insertions (addition of bases), deletions (removal of bases), and chromosomal mutations.
14. The nucleus contains DNA which is transcribed into RNA. The RNA then moves to the ribosomes in the cytoplasm where protein synthesis occurs.
15. A non - coding DNA sequence like a promoter region might be identical during replication and transcription in terms of its sequence being present.
16. Mutation errors can occur during DNA replication, exposure to mutagens (chemicals, radiation), or during DNA repair processes.
17. Disorders in humans can be expressed through changes in protein structure or function due to genetic mutations.
18. If a DNA molecule did not properly replicate, the daughter cells would receive incorrect genetic information, potentially leading to cell death or abnormal cell function.
19. If all the enzymes involved in DNA replication stopped working properly, DNA replication would halt, and the cell would not be able to divide properly.
20. Gene regulation impacts when, where, and how much of a gene is expressed, affecting cell function and development.
21. Sickle Cell Anemia is caused by a point mutation in the beta - globin gene. This mutation causes the production of abnormal hemoglobin, which leads to the characteristic sickle - shaped red blood cells and associated health problems.

Answer:

1. Adenine (A), Thymine (T), Guanine (G), Cytosine (C)
2. Adenine (A), Uracil (U), Guanine (G), Cytosine (C)
3. DNA is double - stranded, has deoxyribose; RNA is usually single - stranded, has ribose.
4. Each new DNA has one old and one new strand.
5. One parental and one new strand per daughter DNA.
6. Hydrogen bonds.
7. DNA: A = T, G = C; RNA is single - stranded, rule not same.
8. Transcription, translation, post - translational mods.
9. RNA polymerase (transcribes), aminoacyl - tRNA synthetase (attaches amino acids), peptidyl transferase (forms peptide bonds).
10. mRNA (carries code), tRNA (brings amino acids), rRNA (part of ribosome).
11. mRNA read by ribosome, tRNA brings amino acids for polypeptide.
12. RNA synthesized from DNA by RNA polymerase.
13. Point (base substitution), insertions, deletions, chromosomal.
14. Nucleus has DNA, RNA moves to ribosomes for protein synthesis.
15. Non - coding like promoter region.
16. During replication, exposure to mutagens, DNA repair.
17. Through changes in protein structure/function due to mutations.
18. Daughter cells get incorrect info, cell death/abnormal function.
19. DNA replication halts, cell can't divide properly.
20. When, where, and how much a gene is expressed.
21. Point mutation in beta - globin gene, causes abnormal hemoglobin and sickle - shaped RBCs.