Which energy producing process is thought to have come first during cellular evolution?
RNA is believed to have been the initial genetic system because it can...
Biological membranes are selectively permeable to control and maintain a cell's internal composition. These types of molecules are able to freely diffuse:
Small uncharged molecules
How many different amino acids comprise the triplet code
This model system is most ideal for investigating plant genetics and biology
Energy yielding reactions are coupled to ATP ______, which energy-requiring reactions are coupled to ATP ____.
Starting with DNA from a single sperm, how many copies of a specific gene sequence will be obtained after 10 cycles of PCR amplification? After 30 cycles?
1024, 1 billion
The most common method of DNA sequencing is based on premature termination of DNA synthesis by inclusion of _______
Phospholipids in a membrane commonly
mover laterally in the plane of the bilayer AND rotate within the bilayer
Eukaryotic cell nuclei contain genes that are
partly archaebacterial and partly eubacterial in origin
The bulk of dry mass of a cell are these kinds of molecules
Feedback inhibition is an example of this mechanism for controlling enzyme activity
The lock and key & induced-fit models are two alternative models that can explain how enzyme and substrates interact. These two models can be distinguished from one another according to changes in ______
Substrate and enzyme shape as binding occurs
Channels form pores through which molecules of appropriate size and charge can cross a membrane whereas carrier proteins
selectively bind small molecules to be transported, change configuration, and release it on the other side
Which of the following organelles will be concentrated in the first pellet produced by differential centrifugation
When cytosine and guanine interact within the DNA molecule, they form
three hydrogen bonds
Trypsin and a D residue in a functionally critical location that is able to form an ionic bond with which amino acids during polypeptide cleavage?
K or R
What is the best technique for looking at overall gene expression within cells?
PCR? or Microarray?
In phospholipids, which of the following is NOT a common structural component?
Restriction endonucleases are enzymes that
cleave DNA only at specific sequences
_____ is the degradation of mRNA by short complementary dbl-stranded RNA molecules
Addition or deletion of one or two nucleotides in the coding part of a gene produces a nonfunctional protein, whereas addition or deletion of three nucleotides often results in a protein with nearly normal function. Explain
Alter reading frame so many incorrect amino acids vs only one
Here is a 6 amino acid peptide: LETWQN. What are the residue names?
- L: Leucine
- E: Glutamic Acid
- T: Threonine
- W: Tryptophan
- Q: Glutamine
- N: Asparagine
Saccarides can form 3 kinds of glycosidic bonds. What are they AND what structure do they produce in eukaryotic systems?
- alpha 1,4: glycogen/starch
- alpha 1,6: branching of glycogen / starch
- beta 1, 4: cellulose
What is the evidence contradicting the central dogma of molecular biology? Explain
Retroviruses have RNA genomes. When retroviruses infect hosts, a DNA copy is synthesized by reverse transcriptase. The central dogma is modified because RNA-> DNA
Provide 6 functional forms of nucleic acids
Transmembrane proteins are generally water soluble. Why do you think this is the case?
The membrane spanning portion of transmembrane proteins are hydrophobic/non-polar amino acids that are dissolved in the lipid bilayer of the membrane. These portions are not soluble in water, therefore the whole protein is insoluble.
List 3 significant differences that distinguish prokaryotic cells from eukaryotic cells.
- Prokaryotes: No nucleus, small circular DNA, no organelles, no cytoskeleton
- Eukaryotes: Nucleus, large linear DNA, organelles, cytoskeleton
If thymine makes up 22% of the bases in a given double stranded DNA molecule, what percentage is made up of cytosines?
Name 3 key components necessary for PCR
- Taq polymerase
Why do scientists believe chloroplasts and mitochondria resemble bacteria
Have their own DNA, own ribosomes, reproduce by simple binary fusion, same size
The human body is composes of more than __ different cell types
Give an example of protein secondary structure
The better you do, the more __ you have