Biology Honors Unit 5 Quiz

• DNA, RNA, Protein Synthesis, and Gene Regulation are covered in Chapter 10.

DNA Experiments and Discoveries

• Griffith discovered a "transforming factor" that could transfer traits between bacteria.
• Hershey and Chase demonstrated that DNA is the hereditary material.
• Franklin's Photo 51 revealed the helical nature of DNA.
• Watson and Crick created the DNA model and base pairing, earning a Nobel Prize.
• Chargaff determined that the amounts of adenine (A) and thymine (T) are equal, as are the amounts of cytosine (C) and guanine (G).
• Avery revealed that DNA is the transforming agent in bacteria.
• One gene makes one specific protein, as shown by Beadle and Tatum.

DNA Structure and Replication

• DNA polymerase, nucleotides, helicase, and ligase play a huge role in DNA structure.
• The sequence of bases determines genes.
• Covalent bonds join nucleotide sequences between sugar and a negative phosphate
• Hydrogen bonds connect bases
• Adenine. Cytosine. Thymine, Guanine are the different bases
• Deoxyribose is the sugar, it is a is 5 carbon ring missing an oxygen atom

Replication

• Parent DNA untwists in the nucleus.
• Then strands separate
• Free bases in cytoplasm attach to complementary bases
• Daughter DNA molecules rewind as it forms, using old DNA as a template for new DNA.
• The leading strand goes towards the unzip, while the lagging strand goes towards the outside, marking Okazaki Fragments.
• DNA Polymerase are enzymes that form covalent bonds between nucleotides of the new strands.
• Proteins can repair DNA at a rate of 50 nucleotides per second, with approximately 1/1 billion incorrectly paired.

DNA Damage

• UV/X rays, toxic chemicals, and viruses can damage DNA.
• All cells share the same genetic information and can pass it down.

RNA Molecules

• RNA Molecules Structure
• RNA polymerase roles
• mRNA is a single-stranded DNA molecule with ribose and uracil (instead of deoxyribose and thymine).
• tRNA includes an anticodon site, an amino acid bonding site, and A and P sites; anticodons decode mRNA for protein translation.
• rRNA is Ribosomal RNA; they fold and start making the ribosomal subunit
• RNA polymerase attaches to the DNA promoter nucleotide sequence on DNA.

DNA vs RNA

• Feature | DNA (Deoxyribonucleic Acid) | RNA (Ribonucleic Acid)
• Sugar | Deoxyribose | Ribose
• Strands | Double-stranded (usually forms a double helix) | Single-stranded
• Nitrogen Bases | Adenine (A). Thymine (T). Cytosine (C). Guanine (G) | Adenine (A), Uracil (U), Cytosine (C), Guanine (G)
• Function | Stores and transmits genetic information | Involved in protein synthesis, gene regulation
• Replication | Self-replicating | Synthesized from DNA (transcription), does not self-replicate
• Enzymes Involved | DNA polymerase | RNA polymerase (for transcription)
• Types | 1 main type | Multiple types: mRNA (messenger), tRNA (transfer), rRNA (ribosomal)
• Location in Cells | Primarily in the nucleus | Found in both the nucleus and cytoplasm

mRNA Processing, Translation, and Protein Synthesis

• Translation
• Amino acid sequencing
• Codon Chart
• Used to translate a codon of mRNA to an individual amino acid
• Amino acids form proteins, and polypeptide chains

Introns

• The uncoded mRNA is usually cut before RNA leaves the nucleus (RNA SPLICING).

Exons

• Coded regions stay when the mRNA leaves the nucleus.

Codon

• A triplet of 3 nucleotides in DNA/RNA for a specific amino acid or signals the start/end of protein synthesis.

Anticodon

• It attaches to the codon in the mRNA sequence
• The other end of the tRNA site allow amino acids to attach
• It is on the tRNA at the ribosomal site itself

Cap & Tail

• They are on the outside and protect Enzymes from cytoplasm by helping ribosomes recognize it as mRNA.

Polypeptide Chain

• Amino acids are from mRNA, and the tRNA pumps them all out
• Also known as proteins

Mutation Definitions

• Mutation is a change in DNA sequence during DNA replication during cell division
• Mutagens may affect the gene translation by amino acid sequence
• Mutation types: Deletion, Addition, substitution

Mutation Results

• Silent mutation (Substitution): Minimal change (GAA to GAG, both Glu)
• Missense mutation (Changed): Impacts occur when one nucleotide is changed (GGC to AGC)
• Frameshift mutation (Deletion/Addition): Shifts in amino acid coding when a nucleotide is added or deleted (GATTACA add mutation to produce GATTAACA)

Gene Regulation

• Genes are regulated by being turned “on and off
• Gene regulations allows for protein productions at the exact right time

Cloning

• Reproductive cloning creates a whole organism: it creates a genetic indentical copy
• Get an egg cell from an animal and remove the nucleus
• Transfer the donor DNA to the empty egg cell.
• Trigger the start of embryo development.
• Transfer the embryo to a surrogate mother.
• Dolly was the first cloned sheep.

Therapeutic Cloning

• Stem cells (embryonic vs adult).
• Grow cells to repair spinal cords + heart attacks
• Embryonic stem cells are grown in a culture, with the option to repair injured or diseased organs, or spinal cord injuries.
• Totipotent - There is some controversy behind if it is moral to remove ES cells that destroy the embryo? And is stem cell modification ethical if it means creating the possibility to "turn into anything" and gain a new function?
• Adult Stem cells can create replacements for cells, but are less versatile than Embryonic cells.
• Pluripotent - Ethical question relating to if we can alter "many things" and what does this mean morally?

Recombinant DNA

• Chapter 12 (pp. 216-237)
• DNA from 2 different sources, and is used in gene cloning

How genes are cloned

• DNA come from 2 sources, resulting in recombinant DNA plasmids
• Bacteria mix those plasmids, bacteria makes a clone of the old gene and is grown in tanks
• Transduction: inserts of DNA from one bacterial cell into another cell
• Translation: fragment to DNA enters from one bacterial cell
• Conjugation: Where the donor shares DNA to the recipient cell and mixes

Genetic Recombination

• Vector
• Cutting DNA with restrictions enzymes, it allows genes to squeeze in
• DNA ligase, glues nucleotides
• Restrictions enzymes, cut DNA for isolation
• Sticky ends are where a cut in DNA has few nucleotides
• Blunt ends, a sequence is unable to access ends
• Cloning Bactria, two different codes of DNA are cut and recombined, then mixed with bacteria and kept in thanks

PCR

• Chain reaction to create copies of a gene to investigate scientific problems
• Mix the DNA nucleotides, sample primers and DNA polymerase, by heating/cooling to separate and reform the DNA.
• Primers are made from strand of Chemically DNA

Gene Cloning

• The duplication of the gene

Probe

• The probe identifies the presence of a nucleotide

Gel Electrophoresis Technology

• Gel electrophoresis is used to separate various strands of DNA from electrophoresis. Electrophoresis is used to investigate any potential crime (such as paternity)

Performing Electrophoresis

• Preparing the Gel Bed, where the edges and bottom need to shut so it is unable to spill, the comb must be placed near the end
• Casting the Gel is done using a cooling agarose solution to fill up the bed
• Preparing the Solidified Gel, slowly remove the tape, slowly pull out the comb and orientate the gel tray, fill the diluted buffer so the Solidified Gel can be submerged.
• Gel loading the Quickstrip using a micropipette is used to load the samples needed
• Running the Gel starts snapping down the terminals and confirming the negative and positive indicators
• Inputting power sources at 125 volts, the electrophoresis must run for 25 minutes.
• Stain the DNA gel using InstaStain and light

Explaining Electroesis

• Bands can be used in DNA fingerprinting, as each band has a unique size that cut be stained for photographs
• DNA fragment (in the gel) show how close a band is to a charge
• Restriction fragments, cut the enzyme
• Agarose gel, the gelatine-like substance for cutting
• DNA Bands are from the DNA profile
• Band migrations show how the DNA moves in relation to a charge
• Forensics, use the DNA testing to confirm paternity or tracking
• Paternity Another, another field based on figuring out who the parents are of a child
• And Genetic Screening, where databases are screened looking for genes

Genetics Research

• Human Genome Project to identify all genes for dna analysis
• Evoluntary relationships between genes in order to find better DNA sequencing.

DNA Technology

• DNA fingerprinting, restriction enzyme analysis + cloning+ PCR
• Tech | Pro | Con
• Biotech Farming hunger can be solved | Could be unhealthy
• Genetically Engineer food | Could be unhealthy + unethical since we are using Animals to get things done we can use plants for
• insulin, growth hormone. vaccines. | Can help with more lives | Can be expensive + misused by parents who want to chose their child based on genes