Genetics Quiz Flashcards
Transcription
Transcription - each gene on the DNA is read and codes directly for an mRNA molecule, mRNA is made by matching its complementary bases to the DNA bases, message is translated to a different nucleic acid language, then mRNA leaves the nucleus and moves to the ribosome
Translation
Translation - ribosome readers the sequence of bases on the mRNA in sets of three called codons, tRNA brings the amino acids to the ribosome as needed, ribosome bonds the amino acids together to build proteins coded for by the gene in the nucleus
role of the ribosome in protein synthesis?
The place where translation occurs, reads the mRNA in codons and makes amino acid sequences based on it
What happens when there is a change in the DNA? How does this affect the protein potentially?
When there is a change in DNA, one or multiple different amino acids can be produced, which can cause an entire protein to fold into the wrong shape and not be able to function correctly
Are all mutations bad? What is a silent mutation?
Not all mutations are bad. Mutations can produce proteins with new or altered functions that can be useful in different or changing environments. A silent mutation occurs when there is a substitution point mutation in Dna, but the substitution in the nitrogenous base results in the production of the same amino acid that the old one did. There is no effect on the protein.
Which of those is a frame-shift mutation? What does this mean?
Insertion and deletion are frame-shit mutations, meaning they cause the rest of the bases after them to get out of alignment. This means they can change every amino acid after the point of mutation, and can alter a protein so much it is unable to perform normal functions.
Polyploidy
heritable condition of possessing more than two complete sets of chromosomes
Mutagen
chemical or physical agents in the environment (which can cause mutations)
general outline of the steps for cloning
Egg cell taken from an adult female sheep, nucleus (so DNA) is removed, donor cell is take from a sheep’s udder, nucleus ius used
Two cells are fused using an electric shock, the fused cell beings dividing normally
The embryo is placed in the uterus of a foster mother, embryo develops into a lamb
different and similar to artificial twinning
Similar to artificial twinning in that it is done artificially, a process to change the birth of organisms, creates organisms which are genetically identical, different in that artificial twinning uses a zygote produced through a natural process
different and similar to asexual reproduction
Similar to asexual reproduction in that it helps to reproduce, different in that it is sexual reproduction, it is an artificial process
Totipotent stem cells
able to develop into any type of cell in the body (can develop into a whole other person if a cell is split off)
Pluripotent stem cells
can develop into any of the body’s cell types but generally cannot form the tissues surrounding the embryo (could not form another person)
Multipotent stem cells
types of differentiated cells they can form are usually limited to replacing cells in the tissues where they are found
Induced pluripotent stem cells (iPSC)
cells that have been converted from normal differentiated cells into cells that closely resemble embryonic stem cells
Sources of stem cells include
Adult stem cells can come from willing donors, embryonic stem cells often come from eggs that were fertilized at in vitro fertilization clinics but never implanted in women’s uteruses, and now some come from the induced pluripotent stem cell technique developed by Shinya Yamanaka
Potential benefits of stem cells
stem cells may make it possible to develop a new field of regenerative medicine, in which undifferentiated cells are used to repair or replace damaged cells and tissues
Ethical concerns of using stem cells
embryonic stem cells are generally obtained in ways that cause the destruction of the embryo, those who seek to protect human embryonic life oppose this research as unethical
describe how the primary structure of proteins determines their overall 3-D shape and thus function
amino acid sequence — drives the folding and intramolecular bonding of the linear amino acid chain, which ultimately determines the protein’s unique three-dimensional shape
dentify important examples of proteins and describe how their structure is related to their function
Hemoglobin, when hemoglobin is mutated, causes red blood cells to change shape, causing sickle cell disease
Explain how genes relate to proteins and how proteins give you traits
DNA → mRNA → amino acid sequence → protein → trait
Genes provide instructions for the assembly of proteins, and proteins execute the blueprint in your DNA to give you the traits your genes specify
DNA composition
Recognizes DNA as a polymer made up of nucleotides. (A,C,T,G)
describe the double-helix shape.
two linked strands that wind around each other to resemble a twisted ladder
3 differences between DNA & RNA.
DNA: double helix (two strands), A C T G, deoxyribose
RNA: single strand, A C U G, ribose
flow of genetic information:
DNA (bases) → mRNA → proteins (amino acids) → trait
From DNA to RNA to amino acid sequence in a protein, a student can trace how a change in one nitrogenous base may affect the resulting protein.
Change in one nitrogenous base would cause the incorrect mutation to be copied into the mRNA, which would then cause the wrong amino acid to be produced, which could throw off the protein by causing it to fold into the wrong shape, potentially stopping it from performing its correct function
Gives an example of a mutation and resulting genetic disorder.
In some people, in the gene for hemoglobin, they have an A nitrogenous base instead of a T, which results in the incorrect amino acid being produced. This results in Sickle Cell Disease. The red blood cells of those with Sickle Cell Disease shrivel and deform, and can block blood flow to the rest of their body.
Recognizes that not all changes in DNA are harmful, and can explain why.
Some changes in DNA are silent mutations, meaning that there is a substitution in a nitrogenous base which still results int he production of the same amino acid. Additionally, some changes in DNA cause beneficial mutations.
