DNA NOTES

Genetic material of cells…

  • GENES – units of genetic material that______
  • Called ______
  • DNA is made up of repeating molecules called ______

A HISTORY OF DNA

  • Discovery of the ______
  • ______– Discovers that a factor in diseased bacteria can transform harmless bacteria into deadly bacteria (1928)
  • ______- X-ray photo of DNA. (1952)
  • ______- described the DNA molecule from Franklin’s X-ray.(1953)

Watson & Crick proposed…

  • DNA had specific pairing between the nitrogen bases:
  • ______-- ______
  • ______-- ______
  • DNA was made of 2 long stands of nucleotides arranged in a specific way called the ______

Nitrogenous Bases

  • PURINES
  • ______
  • ______
  • PYRIMIDINES
  • ______
  • ______

Chargaff’s Rule

  • ______must pair with______
  • ______must pair with______
  • Their amounts in a given DNA molecule will be ______

Genetic Diversity…

  • Different arrangements of______in a nucleic acid (DNA) provides the key to ______among living organisms.

The Code of Life…

  • The “code” of the chromosome is the ______that bases occur.
  • DNA is wrapped tightly around ______and coiled tightly to form chromosomes

DNA REPLICATION

  • DNA must be copied
  • The DNA molecule produces ______new complementary strands following the rules of base pairing: ______, ______
  • Each strand of the original DNA serves as a template for the new strand
  • ______: Watson and Crick showed: the two strands of the parental molecule separate, and each functions as a ______for synthesis of a new complementary strand.

Watson & Crick proposed…

  • DNA controlled cell function by serving as a template for ______structure.
  • 3 Nucleotides = a triplet or ______(which code for a specific AMINO ACID)
  • ______are the building blocks of proteins.

DNA Transcription

  • DNA can “unzip” itself and ______nucleotides match up to the DNA strand.
  • Both DNA & RNA are formed from ______and are called ______acids.
  • The cell uses information from ______RNA to produce proteins

AMAZING DNA FACTS…

  • DNA from a single human cell extends in a single thread for almost 2 meters long!!!
  • It contains information equal to some 600,000 printed pages of 500 words each!!!(a library of about 1,000 books)

RNA AND PROTEIN SYNTHESIS

How your cell makes proteins

  • The production (synthesis) of ______.
  • 3 phases:

1.______

2.______

3.______

  • DNA  RNA  Protein
  • RNA differs from DNA
  • RNA has a ______

DNA has a ______

  1. RNA contains ______

DNA has ______

  1. RNA molecule is ______

DNA is ______

Transcription

  • Then moves along one of the ______and links ______nucleotides together.
  • RNA molecules are produced by copying part of DNA into a ______sequence of RNA
  • This process is started and controlled by an enzyme called ______.

Types of RNA

  • Three types ofRNA:

A.______

B.______

C.______

  • Remember: all produced in the ______!

mRNA

  • Carries ______from DNA to the rest of the ribosome.
  • Tells the ______what kind of protein to ______
  • Acts like an email from the principal to the cafeteria lady

If the cell is a school…

  • The Nucleus is the school office
  • The Nucleolus is the principal’s office
  • The DNA is the principal
  • Ribosomes are the cafeteria ladies
  • mRNA is the email from the principal to the cafeteria lady

rRNA

  • Part of the structure of a ______
  • Helps in ______

tRNA

  • A go-getter.
  • Gets the right parts to make the right protein according to ______

RNA Processing

  • ______are pulled out and ______come together.
  • End product is a ______that leaves the nucleus to the cytoplasm.
  • Introns bad…… Exons good!

Translation - making proteins

  • Three parts:

1.______: start codon (AUG)

2.______:

3.______: stop codon (UAG)

  • Let’s make a ______!!!!.

End Product

  • The end products of protein synthesis is a ______.
  • A sequence of ______bonded together by ______.

Mutation

Objectives:

  • Identify causes of mutation.
  • Compare and contrast types of mutations.
  • Explain how mutations may affect the organisms in which they occur.

Mutation

  • A change in the sequence of bases in DNA or RNA is called a ______.
  • Most people have dozens or even ______of mutations in their ______.
  • Mutations are essential for ______to occur.
  • They are the ultimate source of all ______genetic material in a species.
  • Although most mutations have ______, some are ______, and some are ______causing drastic changes.

Causes of Mutation

  • Some mutations seem to happen ______without any outside influence.
  • They occur when mistakes are made during DNA ______or transcription.
  • Other mutations are caused by ______factors.
  • Anything in the environment that can cause a mutation is known as a ______.

Types of Mutations

  • ______mutations occur in gametes. These mutations are especially significant because they can be ______to offspring and every cell in the offspring will have the mutation.
  • ______mutations occur in other cells of the body. These mutations may have little effect on the organism because they are confined to just one cell and its daughter cells.
  • Somatic mutations ______be passed on to offspring.

Chromosomal Alterations

  • Chromosomal alterations are mutations that change chromosome ______.
  • They occur when a section of a chromosome ______and rejoins incorrectly or does not rejoin at all.
  • Chromosomal alterations are ______.
  • They often result in the ______of the organism in which they occur.

Point Mutations

  • A point mutation is a change in a ______nucleotide in DNA.
  • This type of mutation is usually ______than a chromosomal alteration.
  • Point mutations can be ______mutations
  • The effects of point mutations depend on how they change the ______

Frameshift Mutations

  • A frameshift mutation is a ______of one or more nucleotides that changes the reading frame of the base sequence.
  • Deletions ______nucleotides
  • Insertions ______nucleotides.

Frameshift Mutations Example

  • AUG-AAU-ACG-GCU = start-asparagine-threonine-alanine
  • Let’s say an A nucleotide is inserted after the start codon AUG
  • AUG-AAA-UAC-GGC-U = start-lysine-tyrosine-glycine

Beneficial Mutations

  • They lead to new versions of ______that help organisms adapt to changes in their environment.
  • Beneficial mutations are essential for ______to occur.

Harmful Mutations

  • Any random change in a gene’s DNA is likely to result in a protein that does ______normally or may not function at all.
  • A ______is a disease caused by a mutation in one or a few genes.
  • A human example is ______.
  • ______is a disease in which cells grow out of control and form abnormal masses of cells. It is generally caused by ______in genes that regulate the cell cycle.
  • Cancer genes can be ______.