Learning Objectives 3 for Cells Genes Molecules
Who came up with the double helix theory?
James Watson and Francis Crick
Whose X-ray crystallology work gave James Watson and Francis crick there double helix theory?
What is Semi-conservative?
What Translates to Amino Acids?
What are Codons?
-a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule.
What enzyme is involved with semi-conservative DNA replication
-RNA polymerase(DNA- dependent RNA polymerase)
What are forks in DNA replication?-
-breaks the hydrogen bonds between the two complementary strands of DNA
What is the central dogma?
DNA makes RNA which makes Protein
What is the principle enzyme in transcription?
--RNA polymerase(DNA- dependent RNA polymerase)
What is Transcription?
-Is the process of DNA making RNA
-Results in RNA molecule
What is translation?
- The process of RNA making protein
-Results in Protein
What is folded?
What is responsible for recognizing the intron/exon boundary?
What are Spliceosomes?
-a large and complex molecular machine found primarily within the splicing speckles of the cell nucleus
What are spliceosomes assembled out of?
- from snRNAs and protein complexes
What can 1 gene code for?
-More than one protein
What do mRNA codons do?
-Translate to amino acids at the ribosome
What is translation?
-the process that converts an mRNA sequence into a string of amino acids that form a protein
What is a principle enzyme in Transcription?
What recognizes the intron/extron boundary?
What is an extron
-The protein-coding region in the DNA.
What is an intron
-An intron is a region of mRNA that is going to be removed by splicing b/c it is noncoding
What may mutations arise by?
-Chance errors in DNA replication or by chromosomal arrangement
What are most mutations?
neutral(have no effect on fitness)
What mutations are harmful?
-Mutations that have effect on fitness
What are mutagens?
Chemicals,uv radiation, ionizing radiation
What are beneficial mutations?
-Those that increase fitness
-Tend to increase in frequency in the population
What is positive natural selection
-The chance the frequency will increase in beneficial mutations
What are gain of function mutations?
-Increase the function or amount of encoded protein
What are loss of function mutations?
-Decrease the function or amount of encoded protein
What are more common loss of function mutations or gain of function mutations? why?
-Loss-of-function mutations are more common because it is easier to disrupt the function of a gene than to enhance it.
What are Germinal Mutations?
-occurring in the gonads --->ultimately in the gametes • effects seen in all somatic cells • have evolutionary significance
What are somatic mutations?
-occurring in somatic cells • effects are seen only locally in the body • E.g. derived from mutated stem cells • E.g. tumor cells
What are the types of Mutations?
-Copy number Variation
What are Point Mutations?
-any mutation resulting from nucleotide substitution, or insertion or deletion of one or a few nucleotides (indels)
What are chromosomal Mutations?
-any mutation resulting from a chromosomal rearrangement such as an inversion or translocation.
What are copy number variation mutations?
-individuals of a population vary in the number of copies of large segments of the genome
What is synonymous substitution?
same amino acid
What is missense substitution?
-Different amino acid
What is nonsense substitution?
What is a example of missense point mutation?
What is an example of nonsense point mutation?
What is an example of an Indel mutation?
What are chromosomal rearrangments?
-can disrupt or alter gene function
What gives rise to hemophilia A
What is an example of Copy Number Variant?
What are nucleotides?
-a compound consisting of a nucleoside linked to a phosphate group.
What do nucleotides form?
-the basic structural unit of nucleic acids such as DNA
What forces hold the helix together?
What is base pair complementarity?
-either of the nucleotide bases linked by a hydrogen bond on opposite strands of DNA or double-stranded RNA
What can the nitrogenous base's be in DNA?
What can the nitrogenous base's be in RNA
What does adenine pair with?
-Thymine in DNA
-Uracil in RNA
What does Guanine pair with?
-Cytosine in both DNA and RNA
What bonds the nitrogenous pairs together?
What are Okazaki fragments?
-short, newly synthesized DNA fragments that are formed on the lagging template strand during DNA replication
What happens if mistakes are made in DNA replication
What is the backbone of DNA structure
What is on every sugar in DNA