Ch. 11 - Gene Expression and Epigenetics Flashcards
Hemoglobin is a protein that the blood that binds to and transports oxygen.
True
A hemoglobin molecule is made of _____ polypeptide chain(s).
Four
In the embryo, most hemoglobin molecules consist of _____.
Two epsilon chains and two zeta chains
In the fetus, the expression of the epsilon and _____ chain(s) decreases.
Zeta
In the fetus, the expression of the _____ chain increases.
Alpha
Fetal hemoglobin consists of _____.
Two gamma chains and two alpha chains
Adult hemoglobin consists of _____.
Two alpha chains and two beta chains
Compared to adult blood, fetal blood carries _____ oxygen.
20-30% more
MicroRNAs are typically about _____ bases long.
21
MicroRNAs regulate gene expression at the level of _____.
Translation
MicroRNAs are an example of _____ RNAs.
Noncoding
The human genome contains approximately _____ distinct sequences of microRNAs.
2500
MicroRNAs regulate approximately _____ of the protein-encoding genes in the human genome.
One third
The human genome contains approximately _____ genes.
21,000
Approximately _____ mRNAs can be produced from the information in the human genome.
100,000
Approximately _____ proteins can be produced from the information in the human genome.
One million
_____ explains how one gene can specify multiple mRNAs.
Alternative splicing
Select all of the mechanisms that help to maximize gene expression.
Alternative splicing allows one gene to produce multiple mRNAs.
The intron in one gene’s template strand may form part of the coding strand of a second gene.
Proteins can be modified after translation by the addition of sugars or lipids.
Proteins may be cut after translation to yield two distinct products.
Noncoding RNAs include all types of RNA except the _____.
Messenger RNAs
A _____ is very similar in sequence to a protein-encoding gene and may be transcribed, but is not translated into protein.
Pseudogene
An RNA virus uses an enzyme called _____ to copy its genetic material into DNA.
Reverse transcriptase
A DNA sequence that can move to different locations within the genome is called a ______.
Transposon
You work in a lab and you have discovered a brilliant method for targeted control of chromatin remodeling on a gene-by-gene basis. You are specifically interested in modifying the transcription of oncogenes, which are genes whose overexpression can lead to cancer. Select modifications you would make in cancer cells that are over expressing oncogenes.
Decrease acetylation of histones
Decrease phosphorylation of histones
Increase methylation of histones
You are working in a lab trying to develop a treatment for a novel disease. The exact level of protein produced is very important in the progression of the disease, so you need a mechanism of protein control that allows very fine tuning. Which approach might be helpful in treating this disease?
Using microRNAs to fine-tune protein levels