DNA RNA Protein Synthesis DNA ENGAGE EXPLORE DNA

  • Slides: 37
Download presentation
DNA, RNA & Protein Synthesis

DNA, RNA & Protein Synthesis

DNA

DNA

ENGAGE

ENGAGE

EXPLORE DNA EXTRACTION LAB

EXPLORE DNA EXTRACTION LAB

Rosalind Franklin • In the early 1950 s, British scientist, Rosalind Franklin began to

Rosalind Franklin • In the early 1950 s, British scientist, Rosalind Franklin began to study DNA using Xray diffraction. • She recorded the scattering pattern of the X-rays of DNA. The pattern shows that the strands of DNA are twisted around each other like the coils of a spring (helix).

Watson and Crick • Francis Crick and James Watson were also trying to understand

Watson and Crick • Francis Crick and James Watson were also trying to understand DNA structure. • After seeing Franklin’s X-ray of DNA, Watson and Crick spent a few weeks making a model of DNA. • In April of 1953, they published a historic one-page paper. • Watson and Crick’s model of DNA was a double helix, in which 2 strands were wound around each other.

DNA • DNA was found to code for protein molecules. • Subunit of a

DNA • DNA was found to code for protein molecules. • Subunit of a protein is an amino acid. Amino acids are bound together by peptide bonds to make protein. • Genes are coded DNA instructions that control the production of proteins within the cell. • There is an involved sequence of events that turn the DNA code of nitrogenous bases into protein.

Structure of DNA • DNA is made of subunits (monomers) called nucleotides. • Each

Structure of DNA • DNA is made of subunits (monomers) called nucleotides. • Each nucleotide contains: • A phosphate group • A nitrogen containing (nitrogenous) base • Adenine (A), Guanine (G), Cytosine (C), or Thymine (T) • A sugar called deoxyribose This is one strand of DNA Phosphate group • There are two strands of DNA, making it a double helix • Backbone or sides of the nucleic acid are held together by covalent bonds between the deoxyribose sugar and phosphate. Deoxyribose 1 Nucleotide Nitrogenous bases

Structure of DNA • The nitrogenous bases exhibit complimentary base pairing. • The complimentary

Structure of DNA • The nitrogenous bases exhibit complimentary base pairing. • The complimentary base pairs are: • A to T • G to C • The nitrogenous bases are held together by weak hydrogen bonds.

DNA Replication • In the S phase of interphase, DNA is copied. • Three

DNA Replication • In the S phase of interphase, DNA is copied. • Three steps each with a specific enzyme to control the process: 1. DNA “unzips” (helicase) 2. Free floating nucleotides then base pair to open strands (DNA polymerase) 3. The two new strands “zip-up” and hydrogen bonds form (ligase)

Semi-Conservative Process The original strand (template) is kept.

Semi-Conservative Process The original strand (template) is kept.

ELABORATE DNA MODELS

ELABORATE DNA MODELS

EVALUATE During replication the DNA segment TGCGTACTGATC would produce which complementary strand? A. ACGCATGACTAG

EVALUATE During replication the DNA segment TGCGTACTGATC would produce which complementary strand? A. ACGCATGACTAG B. UGGCAUGACUAG C. ACCGTACTGATC D. ACCGUACUGAUG

EVALUATE Which are the basic units of a DNA nucleotide? A. a pair of

EVALUATE Which are the basic units of a DNA nucleotide? A. a pair of nitrogen bases B. a section of three nitrogen bases C. a single nitrogen base, a sugar, and a phosphate D. a joined pair of nitrogen bases, a sugar, and a phosphate

EVALUATE What is the significance of the sequence of nucleotides? A. It determines what

EVALUATE What is the significance of the sequence of nucleotides? A. It determines what can pass through the phospholipid bilayer in the cell membrane. B. It determines the type of protein being produced. C. It determines the location of the protein shipment. D. It determines the amount of energy required for reactions.

RNA AND PROTEIN SYNTHESIS

RNA AND PROTEIN SYNTHESIS

ENGAGE At your table, discuss the following questions: What is the monomer of a

ENGAGE At your table, discuss the following questions: What is the monomer of a protein? What organelle is where proteins are made? What is the role of DNA in the building of proteins?

EXPLORE PROTEIN SYNTHESIS WEBQUEST

EXPLORE PROTEIN SYNTHESIS WEBQUEST

RNA • RNA (ribonucleic acid) plays an important part in protein synthesis • RNA

RNA • RNA (ribonucleic acid) plays an important part in protein synthesis • RNA is a single stranded molecule made of nucleotides • The RNA nucleotides are similar to the nucleotides found in DNA. They contain a: • Phosphate group • 5 -carbon sugar called ribose • Nitrogen containing bases • Adenine • Guanine • Cytosine • Uracil (instead of thymine)

Central Dogma DNA → RNA → protein → trait

Central Dogma DNA → RNA → protein → trait

Protein Synthesis • RNA is a short-lived molecule. Its main function is to copy

Protein Synthesis • RNA is a short-lived molecule. Its main function is to copy DNA and transfer the DNA code into a protein molecule. • The process of making protein can be divided into two parts: • Transcription -m. RNA (messenger RNA) carries copies of the DNA molecule from the nucleus into the cell cytoplasm. • Translation - t. RNA (transfer RNA) transfers an amino acid to the ribosome after receiving the code from m. RNA. The amino acids are put together on the ribosome to make a protein. • Ribosomal RNA (r. RNA) - Helps bind m. RNA and t. RNA together during protein synthesis

Protein Synthesis Transcription and Translation

Protein Synthesis Transcription and Translation

Protein Synthesis

Protein Synthesis

The Genetic Code • A codon designates an amino acid. • An amino acid

The Genetic Code • A codon designates an amino acid. • An amino acid may have more than one codon. • There are 20 amino acids, but 64 possible codons • Some codons tell the ribosome to stop translating. • The 3 bases of an anticodon are complementary to the 3 bases of a codon. • Example: Codon ACU Anticodon UGA

Genetic Code • What amino acid does GAA code for? • Glutamic acid •

Genetic Code • What amino acid does GAA code for? • Glutamic acid • What amino acid does UCU code for? • Serine • What amino acid does AAA code for? • Lysine • What amino acid does UGA code for? • None, it is a stop sequence

Proteins 3 D shape determines its function Proteins can be Structural forming part of

Proteins 3 D shape determines its function Proteins can be Structural forming part of the cell material Proteins can be functional ex: hormones, enzymes or involved in lowering activation energy Amino Acid Sequence- forms a protein that leads to a specific function

Protein Production Cells respond to their environment by producing different types and amounts of

Protein Production Cells respond to their environment by producing different types and amounts of protein. 1. Overproductions of Protein Advantage: Injury Repair Disadvantage: Cancer 2. Underproduction of proteins Ex: hyperglycemia, hypo-thyroid 3. Production of proteins at the incorrect times Ex: hypoglycemia

Mutations • Mutations are changes in the genetic code. • Mutation change the amino

Mutations • Mutations are changes in the genetic code. • Mutation change the amino acid sequence and thus changes the protein • Can be caused by mutagens or things in the environment that cause changes in DNA. • Exposure to chemicals, radiation, disease, and other factors.

Mutations • Deletions - Nucleotide is missing • Insertions (additions) - DNA is added

Mutations • Deletions - Nucleotide is missing • Insertions (additions) - DNA is added • Substitutions - DNA is changed from one base to another

Mutations • Mutations affect function and phenotype. • A few mutations are actually beneficial.

Mutations • Mutations affect function and phenotype. • A few mutations are actually beneficial. In plants, chromosomes do not always separate to form a diploid (2 n) organism. Sometimes they are triploid (3 n) or polyploid. These plants often have important characteristics (more petals, more starch, etc. ).

ELABORATE RE-ENACT PROTEIN SYNTHESIS

ELABORATE RE-ENACT PROTEIN SYNTHESIS

EVALUATE Which is the process of using a DNA template to make m. RNA?

EVALUATE Which is the process of using a DNA template to make m. RNA? A. Transcription B. Translation C. Replication D. Differentiation

EVALUATE A segment of the DNA from a chimpanzee has the sequence: TAC GAA

EVALUATE A segment of the DNA from a chimpanzee has the sequence: TAC GAA GCA. Which m. RNA would be transcribed from this segment of DNA? A. GCA TCC TAC B. AUG CUU CGU C. TAC GAA GCA D. CAT CTT GGA

EVALUATE What is the function of transfer RNA? A. It is a part of

EVALUATE What is the function of transfer RNA? A. It is a part of the ribosome. B. It bonds to other RNA molecules, leading to their destruction. C. It carries the information coding for the amino acid sequence of a protein. D. It delivers the correct amino acid to the ribosome.

EVALUATE What type of mutation occurs when a piece of a chromosome is lost

EVALUATE What type of mutation occurs when a piece of a chromosome is lost during cell division? A. Insertion B. Deletion C. Substitution D. Iversion

EVALUATE Which would most likely produce a mutation that is passed on to offspring?

EVALUATE Which would most likely produce a mutation that is passed on to offspring? A. radiation changing the DNA sequence in skin cells B. tobacco smoke altering the genes in lung cells C. exposure to chemicals altering nerve cell function D. a sperm cell with a missing chromosome