BIOL 3410 Chapter Notes - Chapter 4, 11, 12: Trypsin, Column Chromatography, Lipid Bilayer

28 views4 pages

burgundyweasel733

22 Dec 2016

School

Department

Course

Professor

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

Document Summary

Chapter 4: the shape and structure of proteins. Proteins fold into a conformation of lowest energy. Can be denatured by treatment with solvents that disrupt the noncovalent interactions. When solvent is removed, the protein often refolds spontaneously, known as renaturation. Tend to form aggregates, many times causing death. Chaperone proteins(molecular chaperones): proteins that assist protein folding in a living cell. These proteins bind to partly folded pp chains and help them progress along the most energetically favorable folding pathway. Found in the protein -keratin, which is abundant in skin and its derivatives such as hair, nails, and horns. Resembles a spiral staircase and can be either right- or left- handed. Handedness not affected if upside-down but is if reflected in a mirror. Generated when single polypeptide chain turns around itself to form a structurally rigid cylinder. H-bond at every 4th aa, (cid:272)o(cid:373)plete e(cid:448)ery 3. 6 aa"s: sheet.

Related Questions

Protein Structure

a.Different function of proteins and examples:

b. Protein building blocks:

1. atomic composition of building block:

2. "parts" or "functional groups" of the building block:

c. Importance of side chain (R group):

d. Hydrophobic amino acids characteristics:

e. Hydrophilic amino acids characteristics:

f. Charged amino acids characteristics

Copy and complete the table below regarding the characteristics and which groups in the polypeptide interact together at each structural level of the protein.

	characteristics	groups interacting
Primary structure
Secondary structure
Tertiary structure
Quartenary structure

Value: 2

Choose the correct statement(s). You may choose more than one answer.

[mark all correct answers]
a. Proteins are the building blocks of amino acids.

b. Enzymes are a type of protein.

c. Quartenary structure consists of two or more polypeptide chains interacting.

d. Amino acids are made of carbon, hydrogen, nitrogen and phosphorus.

e. The primary structure of a protein is formed due to the interaction of side groups.

Value: 3

Put the following statements regarding the structural levels of a protein formation in the correct order.

Below is a sequence of events. Place them in the order they should occur, number 1 being the first item. Select the step number from the drop down next to each item.

Items to order:

1. Individual amino acids are bonded together via peptide bonds.

2. Two or more polypeptide chains interact via bonds.

3. Hydrogen bonds form between neighboring amino acids within a polypeptide chain allowing the chain to coil or form pleated sheets.

4. Side groups (R) of the individual amino acids interact with each other allowing the protein to assume its three dimensional shape.

Value:4

Put the following statements regarding the structural levels of a protein formation in the correct order

Individual amino acids are bonded together via peptide bonds.	1 2 3 4
Two or more polypeptide chains interact via bonds.	1 2 3 4
Hydrogen bonds form between neighboring amino acids within a polypeptide chain allowing the chain to coil or form pleated sheets.	1 2 3 4
Side groups (R) of the individual amino acids interact with each other allowing the protein to assume its three dimensional shape.	1 2 3 4

Value: 5

Hydrophobic amino acids will be found _______________.

a. In the interior (inner core) of a protein, away from the watery environment.

b. in the interior of a plasma membrane.

c. Both A and B

d. Neither

Value: 6

A protein's function is defined by ____________.

a. enzymatic reactions

b. it's shape.

c. chain of nucleotides.

d. the presence of carbon and hydrogen.

Value: 7

Which of the following is NOT considered a protein function?

a. transport of substances across membrane

b. enzymatic reactions

c. provides structural support

d. carries genetic information

16.Globular proteins fold up into compact, spherical structures that have uneven surfaces. They tend to form

multisubunit complexes, which also have a rounded shape. Fibrous proteins, in contrast, span relatively large

distances within the cell and in the extracellular space. Which protein is not classified as a fibrous protein?

(a)elastase (b)collagen (c)keratin (d)elastin

17.You have two purified samples of protein Y: the wild-type (nonmutated) protein and a mutant version with a

single amino acid substitution. When washed through the same gel-filtration column, mutant protein Y runs through

the column more slowly than the normal protein. Which of the following changes in the mutant protein is most likely

to explain this result?

(a)the loss of a binding site on the mutant protein surface through which protein Y normally forms dimers

(b)a change that results in the mutant proteinâs acquiring an overall positive instead of a negative charge

(c)a change that results in the mutant proteinâs being larger than the wild-type protein

(d)a change that results in the mutant proteinâs having a slightly different shape from the wild-type protein

18.Which of the following statements is true?

(a)Disulfide bonds are formed by the cross-linking of methionine residues.

(b)Disulfide bonds are formed mainly in proteins that are retained within the cytosol.

(c)Disulfide bonds stabilize but do not change a proteinâs final conformation.

(d)Agents such as mercaptoethanol can break disulfide bonds through oxidation.

19.Proteins bind selectively to small molecule targets called ligands. The selection of one ligand out of a mixture of

possible ligands depends on the number of weak, noncovalent interactions in the proteinâs ligand-binding site. Where

is the binding site typically located in the protein structure?

(a)on the surface of the protein (b)inside a cavity on the protein surface

(c)buried in the interior of the protein (d)forms on the surface of the protein in the presence of ligand

thanks

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