BIOSC 1000 Lecture Notes - Lecture 5: Guanidinium Chloride, Mhc Multimer, 2-Mercaptoethanol

49 views9 pages

carminebutterfly755

1 Feb 2017

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Primary protein structure is the amino acid sequence from amino- to carboxyl- terminus. Secondary structure is the local spatial arrangement of a polypeptide"s backbone atoms in a segment of the peptide chain does not take into account the conformations of side chains repeating patterns dictated by bond angles (peptide bond has resonance) The planar nature of peptide bonds constrains the conformation of a polypeptide chain every peptide bond has a phi/psi angle. The trans orientation around a peptide bond is favored the trans orientation has less steric hindrance than the cis orientation. Proline and glycine are the two amino acids that adopt the cis conformation. Glycine is in the cis orientation does not have much hindrance because r group is just an h. Proline cyclizes back on itself and forces itself a cis conformation. There is free rotation about the other bonds in a polypeptide backbone. C(alpha)-nh angle is the phi angle - amino group.

Related Questions

1. A sequence of amino acids in a certain protein is found to be â Ser â Gly â Pro â Gly â

The sequence is most probably part of a(n):

a. beta turn

b. antiparallel beta sheet

c. alpha-helix

d. parallel beta-sheet

e. alapha-sheet

2. Which statement about peptides bonds is NOT TRUE?

There is perfectly free rotation about the peptide bond.

The peptide bond has partial double-bond character.

The peptide bond is shorter than a normal carbon-nitrogen single bond.

The peptide bond usually has a trans configuration with respect to the alpha-carbons of the two amino acids involved in the peptide bond.

Peptide bonds are made via condensation of an amine and a carboxylic acid with loss of water.

3. Which of the following statements about proteins is FALSE?

	Active proteins are generally very loosely structured.
	In water-soluble proteins, hydrophobic amino acid residues are generally buried and not exposed to water.
	Primary structure determines tertiary structure.
	Secondary structure is regular, recurring arrangements in space of nearby amino acid residues in a polypeptide.
	Quaternary structure involves the interaction of subunits in a protein with more than one polypeptide chain.

maroonwallaby335

1. In biology, the term "ionic bond" is used differently than inchemistry. A biological "ionic bond" is used to describe theinteraction of an R group containing a carboxyl group(âCOO^â) with an R group containing an amino group(âNH₃⁺). From this description, what do youunderstand a biological "ionic bond" to be?

a. van der waals interaction

b. hydrogen bond

c. Electrostatic interaction

d. covalent bond

2. The three dimensional arrangement of alpha helices,beta-sheets and other parts of the polypeptide chain is called

a. primary structure

b. secondary strucutre

c. tertiary structure

d. quaternary structure

3. Multiple polypeptide chains are held together by

a. peptide bond

b. intermolecular forces

4. What holds multiple polypeptides together? (Choose bestanswer)

a. R groups

b. amino groups

c. carboxylate group

5. Which of the following single-celled organisms is an exampleof a prokaryote?

a. algae

b. yeast

c. amoeba

d. bacteria

6. Which of the following is an insect most closely relatedto?

a. tree

b. mushroom

c. fish

d. bacteria

7. In evolutionary history, which was the most ancientdivergence?

a. Prokaryotes and eukaryotes

b. Birds and reptiles

c. Rats and mice

d. Plants and animals

8. In evolutionary history, which was the most recentdivergence?

a. Prokaryotes and eukaryotes

b. Birds and reptiles

c. Rats and mice

d. Plants and animals

9. What is the chemical equation for ATP synthesis?

a. ADP + P_i â¶ ATP + H₂O

b. ATP + H₂O â¶ ADP + P_i

_c. ADP + H₂O â¶ ATP + P_i

_d. ATP + P_i â¶ ADP +H₂O

9. What is glycolysis?]

a. It is the oxidation of three-carbon molecules into carbondioxide.

b. It is the splitting of six-carbon sugars into three carbonmolecules with the synthesis of ATP.

c. It is the transport of electrons to power the synthesis ofATP.

d. It is the synthesis of sugars from carbon dioxide.

10. What chemistry concept describes whether a reaction orprocess can occur spontaneously?

a. therodynamics

b. kinetics

mauvetortoise304

Question 401 pts

Kinetic energy is the stored energy that can be used for motion.

True

False

Flag this Question

Question 411 pts

When an electron is transferred from one atom to another, and the two atoms are then electrically attracted to one another, a(n) ________________ bond is formed.

Flag this Question

Question 421 pts

Changing the number of ____________ of an atom would change the chemical properties of the atom.

Flag this Question

Question 431 pts

Forming molecules and breaking down molecules in biological organisms usually requires the use of _________ to help the reaction proceed faster.

Flag this Question

Question 441 pts

Organic molecules have a core composed of .

Flag this Question

Question 451 pts

The building blocks of carbohydrates are

Flag this Question

Question 461 pts

Water molecules crossing a membrane from high to low concentration is .

active transport

cell fate

facilitated diffusion

osmosis

Flag this Question

Question 471 pts

Choose the membrane molecule responsible for the passage of polar molecules and ions into and out of the cell.

phospholipids

transmembrane channel proteins

cell surface proteins

carbohydrate chains

Flag this Question

Question 481 pts

The simplest cells are .

Flag this Question

Question 491 pts

Which of the following membrane bound organelles are found inside bacterial cells:

nucleus

organelles are not found in prokaryotic cells

mitochondria

chloroplasts

Flag this Question

Question 501 pts

Which of the following is a specialized components of the cell, is associated with the rough endoplasmic reticulum, and is responsible for making proteins.

Flag this Question

Question 511 pts

Proteins are sorted, modified, and packaged by the _____________ and later transported to the outside of the cell.

ribosomes

golgi bodies (golgi apparatus)

nucleus

mitochondria

Flag this Question

Question 521 pts

Dehydration synthesis is a process of linking two smaller subunits together to form a polymer. Which of the following statements below is true of dehydration synthesis?

Oxygen is consumed.

A water molecule is removed from the molecules.

A water molecule is added to the molecules

Carbon dioxide is given off.

Flag this Question

Question 531 pts

Proteins are made up of _________ held together by peptide bonds.

Flag this Question

Question 541 pts

Which of the following gives an amino acid its properties?

NH2

R Group or functional group

COOH

Flag this Question

Question 551 pts

The final three-dimensional shape of a protein that includes the bonding of two or more polypeptide chains is call its _____ structure.

Flag this Question

Question 561 pts

How do DNA and RNA differ?

all statements are differences between DNA and RNA.

DNA is double stranded while RNA is single stranded.

They have different sugars.

Thymine is present in DNA but not in RNA.

Flag this Question

Question 571 pts

Which of the following is a component of a DNA nucleotide?

phosphate

a nitrogen containing base

All are components of a nucleotide.

5-carbon sugar

Flag this Question

Question 581 pts

Cell membranes are made up of several different types of molecules. Select the membrane molecule below that is made up of a polar region and two non-polar fatty acid tails.

transmembrane proteins

carbohydrate chains

phospholipids

cell surface proteins

Flag this Question

Question 591 pts

Two organelles which are believed to have once been free-living bacterial cells are ____________ and ______________.

chloroplasts and mitochondria

golgi apparatus and endoplasmic reticulum

ribosomes and nucleolus

peroxisomes and lysosomes

Flag this Question