1. Introduction to Biology

2. Chemistry

3. Water

4. Biomolecules

5. Cell Components

6. The Membrane

7. Energy and Metabolism

8. Respiration

9. Photosynthesis

10. Cell Signaling

11. Cell Division

12. Meiosis

13. Mendelian Genetics

14. DNA Synthesis

15. Gene Expression

16. Regulation of Expression

17. Viruses

18. Biotechnology

19. Genomics

20. Development

21. Evolution by Natural Selection

22. Evolution of Populations

23. Speciation

24. History of Life on Earth

25. Phylogeny

26. Prokaryotes

27. Protists

28. Plants

29. Fungi

30. Overview of Animals

31. Invertebrates

32. Vertebrates

33. Plant Anatomy

34. Vascular Plant Transport

35. Soil

36. Plant Reproduction

37. Plant Sensation and Response

38. Animal Form and Function

39. Digestive System

40. Circulatory System

41. Immune System

42. Osmoregulation and Excretion

43. Endocrine System

44. Animal Reproduction

45. Nervous System

46. Sensory Systems

47. Muscle Systems

48. Ecology

49. Animal Behavior

50. Population Ecology

51. Community Ecology

52. Ecosystems

53. Conservation Biology

[BOOK BIO] CLUTCH

Denaturation breaks the covalent bonds that hold the protein in its three-dimensional shape. Without the proper shape, the protein cannot function.

No. The covalent bonds that determine the protein's primary structure are not disrupted during denaturation, but these are not the bonds that hold the protein in its three-dimensional shape.

Denaturation destroys the primary structure of the protein, and the protein breaks down to monomers.

No. Primary protein structure is generally not affected during denaturation.

Different amino acids are substituted into the sequence, so the protein's properties change.

No. Denaturation does not involve substitution of amino acids.

The protein's pH changes, and the change causes the protein to lose its functionality.

No. Changes in pH may cause a protein to denature. Denaturation does not change the pH of the protein.

Denaturation breaks the intramolecular bonds, such as hydrogen bonds and van der Waals interactions, that hold the protein in its three-dimensional shape. Without the proper shape, the protein cannot function.

Think of the bonds and interactions that influence the shape of a protein.

When a protein is denatured, why does it lose its functionality?

Make a concept map (see BioSkills 12) that relates the four levels of protein structure and shows how they can contribute to the formation of hemoglobin. Your map should include the following boxed terms: Primary structure, Secondary structure, Tertiary structure, Quaternary structure, Amino acid sequence, R-groups, αα-helices, and ββ-pleated sheets.<img src="https://lightcat-files.s3.amazonaws.com/problem_images/d22c624af515c4fe-1667314475308.jpg" alt="" />

Proteins

Post-Translational Modification of Proteins

No. DNA is a polymer of nucleotides. What is the monomer used to form a protein?

No. Fatty acids are a component of triacylglycerols (fats) and phospholipids.

No. Purines and pyrimidines are nitrogenous bases present in nucleotides, the monomers of nucleic acids.

Which polymers go with which monomers?

Protein molecules are polymers (chains) of __________.

No. The double helix is the shape associated with the nucleic acid DNA.

No. The primary structure is the polypeptide's sequence of amino acids.

No. Although the secondary structure involves three-dimensional shapes, these shapes are confined to small regions of the polypeptide.

No. Quaternary structure is a feature of proteins that consist of two or more polypeptide chains, each with its own tertiary structure, combined to form a single functional protein.

Review the levels of protein structure. .

The overall three-dimensional shape of a single polypeptide is called its __________.

What type of information is used to direct different polypeptides to fold into different shapes?

Animation: Protein Functions

Post-translational Modifications and Chaperone Proteins

Structure and function of Biological Macromolecules

Which two functional groups are always found in amino acids?a) Carbonyl and amino groups.b) Carboxyl and amino groups.c) Amino and sulfhydryl groups.d) Hydroxyl and carboxyl groups.

Based on what you know of the peptide bonds that link together amino acid residues, why would proline's side chain reduce the flexibility of the backbone?

Post Translation Modification

The specific amino acid sequence in a protein is its:a) Primary structure.b) Secondary structure.c) Tertiary structure.d) Quaternary structure.

Animation: Protein Structure

The primary building blocks (monomers) of proteins are:&nbsp;a) Glucose molecules.b) Lipids.c) Nucleotides.d) Amino acids.e) None of these.

Protein Structure

a hydrogen bond joining amino acids together to form a polypeptide

No. Peptide bonds are not weak interactions, such as hydrogen bonds.

a covalent bond joining simple sugars together to form a polypeptide

No. Peptide bonds do not link simple sugars together.

a hydrogen bond joining nucleotides together to form a nucleic acid

No. A peptide bond is not a hydrogen bond, and it does not join nucleotides together.

a covalent bond joining nucleotides together to form a nucleic acid

No. Nucleotides are joined together by phosphodiester linkages, not peptide bonds.

a covalent bond joining amino acids together to form a polypeptide

Consider the specific types of bonds present in the four types of macromolecules present in living systems.

The peptide bond is __________.

The structural level of a protein least affected by a disruption in hydrogen bonding is the
a. primary level.
b. secondary level.
c. tertiary level.
d. quaternary level.

Short Video: Cotranslational Transport

Biomolecules: The Proteins

Different proteins are composed of different sequences of                   .
a. sugars;
b. lipids;
c. fats;
d. amino acids;
e. carbohydrates

If a cell were to use only 10 of the 20 possible amino acids, how much effect would you expect this to have on protein diversity? Calculate and compare the number of different sequences that can be generated by randomly assembling either 10 or 20 amino acids into peptides that are five residues long.

Assist in dehydration synthesis reactions.

Assist in protein folding or re-naturing.

What is the role of a chaperone protein?a) Assist in RNA and DNA folding.b) Assist in membrane transport.c) Assist in protein denaturation.d) Assist in dehydration synthesis reactions.e) Assist in protein folding or re-naturing.

Amino Acids

BioFlix: Protein Modifications

Post Translational Modifications

Why are proteins not considered to be a good candidate for the first living molecule?
a. Their catalytic capability is not sufficient for most biological reactions.
b. Their amino acid monomers were not likely present in the prebiotic soup.
c. They cannot serve as a template for replication.
d. They could not have polymerized from amino acid monomers under early Earth conditions.

the &alpha; helix or &beta; pleated sheets

No. Both the &alpha; helix and &beta; pleated sheets are types of secondary structure.

interactions among the side chains or R groups of the amino acids

No. These contribute to the tertiary structure of a polypeptide.

coiling due to hydrogen bonding between amino acids

No. This contributes to the secondary structure of a polypeptide.

the weak aggregation of two or more polypeptide chains into one functional macromolecule

No. This refers to the quaternary structure of a protein.

the sequence of amino acids along a polypeptide chain

Consider which of these is the simplest level of protein structure.

The "primary structure" of a protein refers to __________.

Organic molecules linked by dehydration reactions

No. This is also true of some carbohydrates and lipids.

No. Amino acids in a polypeptide are linked by dehydration reactions, not hydrolysis (which would separate them).

Carbohydrates with a hydrogen bond holding them together

No. Polypeptides are proteins, not carbohydrates.

Consider the meaning of the prefix poly- and the suffix -peptide.

Which of the following represents a specific description of a polypeptide?

Explain how molecular chaperones facilitate protein folding in many different polypeptides, each with their own specific shape.

No. The primary structure is the sequence of amino acids.

No. The tertiary structure is the overall three-dimensional shape of a polypeptide resulting from interactions between the R groups (side chains) of the various amino acids (hydrophobic interactions, hydrogen bonds, ionic bonds, and disulfide bridges).

No. The quaternary structure is the aggregation of two or more polypeptide chains into one functional protein macromolecule.

No. There is no such thing as a pentiary structure in a protein.

Consider size and the proximity of amino acids involved of these structures relative to the whole protein.

The &#945; helix and &#946; pleated sheet represent which level of protein structure?

What type of bond is directly involved in the formation of an α-helix?
a. peptide bonds between amino acid residues
b. hydrogen bonds between amino acid residues
c. van der Waals interactions between nonpolar residues
d. disulfide bonds between cysteine residues

5 Protein-Related Terms

Peptide bonds join the amine group on one amino acid with the R group of another amino acid.

Secondary protein structures are caused by hydrogen bonding between atoms of the peptide backbone.

Tertiary protein structure emerges when there is more than one polypeptide in a protein.

Which of the following is true of protein structure?a) Peptide bonds are formed by hydrolysis.b) Peptide bonds join the amine group on one amino acid with the R group of another amino acid.c) Secondary protein structures are caused by hydrogen bonding between atoms of the peptide backbone.d) Tertiary protein structure emerges when there is more than one polypeptide in a protein.

No. A denatured protein is one whose shape has changed to the point that it cannot be catalytic, but there is a better answer.

No. Salt concentration and pH changes may indeed change the shape and, therefore, the catalytic function of an enzyme, but there is a better answer.

No. Heating the protein may indeed change the shape and, therefore, the catalytic function of an enzyme, but there is a better answer.

Treating the protein with a chemical that breaks hydrogen bonds

No. Breaking hydrogen bonds would alter the shape of an enzyme and might therefore change its catalytic function, but there is a better answer.

Consider what factors are responsible for the shape of a polypeptide or protein.

Enzyme molecules require a specific shape to perform their catalytic function. Which of the following might alter the shape of an enzymatic protein?

No. Sucrose is a disaccharide, and glucose is a monosaccharide.

No. Water has only three atoms; it must be at the beginning of this ranking.

No. Proteins are typically assembled from many amino acids. Expect to see protein at the end of the ranking.

Keep your monomers and polymers straight. and

Which of the following lists ranks these molecules in the correct order by size from smallest to largest?

Proteins | Biological Molecules Simplified #2

Which structural level of a protein would be least affected by a disruption in hydrogen bonding?
a. primary structure
b. secondary structure
c. tertiary structure
d. quaternary structure

Animation: Proteins

Most proteins are soluble in the aqueous environment of a cell. Knowing that, where in the overall three-dimensional shape of a protein would you expect to find amino acids with hydrophobic R groups?

How can a cell make many different kinds of proteins out of only 20 amino acids? Of the myriad possibilities, how does the cell 'know' which proteins to make?

#1 A Level Biology - Biological Molecules

Denatured Proteins & Chaperones

What are the two types of secondary structures found in polypeptides, and what maintains them? What stabilizes the tertiary structure of a polypeptide?

Predict the effect on protein function if each polypeptide adopted only a single, inflexible shape based on its primary structure.

Protein Structure and Folding

What term is used for an amino acid chain that has greater than 50 covalently linked amino acids?a) Protein.b) Peptide.c) Amino acid.d) Polypeptide.

Major Elements in Biological Molecules: Proteins

Post Translational Modifications Of Proteins

Properties of Biological Macromolecules | AP Biology 1.4

Proteins may function as                   .
a. genetic material;
b. cholesterol molecules;
c. fat reserves;
d. enzymes;
e. all of the above

All cause the misfolding of nucleic acids.

No. All of these are associated with another category of macromolecules.

All are associated with plaque buildup in arteries (atherosclerosis).

No. A high level of cholesterol in the blood is thought to contribute to atherosclerosis.

All are caused by the buildup of misfolded proteins in cells.

No. It is not known for certain that the buildup of misfolded proteins in the brain causes each of the three diseases.

All are associated with the buildup of lipids in brain cells due to faulty lysosome activity.

No. It is not the buildup of lipids that associates these diseases.

All are associated with the buildup of misfolded proteins in cells.

Consider the cause more than the symptoms.

What do Alzheimer's, Parkinson's, and mad cow disease have in common?

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