Place the following steps of TRANSLATION in the correct order for EUKARYOTES.
The ribosome reaches a stop codon. A release factor binds and causes the release of the new polypeptide, along with the mRNA. The ribosome dissociates.
-
The ribosome moves exactly 3 nucleotides toward the 3' end of the mRNA.
The small ribosomal subunit binds the mRNA near the 5' end and begins to search for the start codon.
A charged tRNA with a matching anticodon binds the mRNA codon in the A site.
The initiator tRNA binds to the small ribosomal subunit.
The ribosome catalyzes the formation of a peptide bond between the amino acids held by the tRNA in the P site and the new amino acid on the charged tRNA in the A site. This tRNA ends up holding the whole chain of amino acids.
The small ribosomal subunit uses rRNA to bind to the Kozak sequence, which places the initiator tRNA on the start codon and in the P site.
The large ribosomal subunit joins the small subunit, ending the
Initiation phase.
In: Biology
Multiple or none of the answers may be correct:
The affinity of a protein for a ligand
| a. |
Changes as a function of the ligand concentration |
|
| b. |
Is described by the Kd |
|
| c. |
Is governed at the molecular level by weak interactions between the protein’s amino acids and the functional groups on the ligand |
|
| d. |
Is a measure of the tightness of the binding interaction |
The following statements about enzyme inhibitors are TRUE:
| a. |
Mixed inhibitors bind at a second site |
|
| b. |
Competitive inhibitors bind at the active site |
|
| c. |
Suicide inhibitors irreversibly (covalently) attach to the active site |
|
| d. |
Uncompetitive inhibitors bind at the active site |
The following statements about protein secondary structure are TRUE:
| a. |
Beta sheets may have parallel or anti-parallel strands |
|
| b. |
Alpha helices are always right-handed |
|
| c. |
Beta sheets form hydrogen bonds between the carbonyl groups on one strand and the carbonyl groups on the opposite strand |
|
| d. |
Alpha helices are always stabilized by interactions between parallel helices |
In: Chemistry
A deletion mutation occurs, leaving 11 bases in nucleotide sequence. What is the maximum number of amino acids that could be coded for by this sequence? Question 8 options: 3 4 6 11 ? Why?
In: Biology
Coenzymes differ from enzymes, in that coenzymes
Select one:
a. are active only outside the cell.
b. are polymers of amino acids.
c. are specific for one reaction.
d. bind to the active sites of enzymes.
In: Biology
5. Glycolysis has 10 steps. Draw out the reaction for a. One step that is catalyzed by a kinase. b. One step that is catalyzed by an isomerase. c. One step that is catalyzed by a dehydrogenase. In each case, make sure to include which step you are drawing, the name of the enzyme, and the structures of the reactants and products.
In: Biology
Problem Title: Peptide Sequencing (Intro to Biochemichemistry)
#1:
Hydrolysis of dodecapeptide P
with the enzyme trypsin affords the following fragments:
Pro-Thr-Phe-Phe-Tyr-Ala-Arg, Asp-Asn-Arg,
His-Arg.
Hydrolysis with chymotrypsin yields: Phe, Tyr,
His-Arg-Pro-Thr-Phe, Ala-Arg-Asp-Asn-Arg.
What is the amino acid sequence of P? ___
________________
#2:
Hydrolysis of nonapeptide P
with the enzyme trypsin affords the following fragments:
Glu-Ser-Arg, Glu-Tyr-Ser-Phe-Ala-Arg.
Hydrolysis with chymotrypsin yields: Glu-Tyr, Ser-Phe,
Ala-Arg-Glu-Ser-Arg.
What is the amino acid sequence of P? ___
In: Chemistry
-Substrate-level phosphorylation occurs in __________ and __________ steps of glucose catabolism. Additionally, the other mechanism of ATP, ___________ occurs as a result of the __________ .
-In _______ C6H12O6 is converted to _________ . In _________the carbons on acetyl-CoA are released as __________ . In the ________ , O2 is converted to ________ by accepting the electrons at the end.
-At the start glycolysis, the electrons are (high/low) energy and are found in _______ molecules. These electrons (gain/lose) energy as they are transferred to __________. _________ carries these (high/low) energy electrons to the mitochondria where they are sent through the electron transport chain and end up on ________ molecules. By the end, these electrons are (high/low) energy.
-At the start of glycolysis, glucose (gains/loses) energy when 2 ATP are ______ . After this, ________(#) ATP are produced in glycolysis, making the net ATP production _____ (#) ATP molecules are e in pyruvate oxidation and _____ are made in the TCA cycle. ~30 ATP molecules are made as the result of ________ where the electrochemical gradient powers the enzyme _________ .
In: Biology
In: Biology
Describe the properties of an amphipathic alpha helix and identify numbered amino acids in a dodecamer polypeptide that contribute to the chemical properties of this secondary protein structure. Where are amphipathic alpha helices found in a globular cytosolic protein?
In: Biology
Urea Cycle:
a. What is its main purpose?
b. Which 2 amino acids feed directly into the cycle?
c. What cellular location does it occur in?
d. Does it create or use ATP?
In: Biology