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Flashcards in Proteins Deck (42):
1

The shape of a protein molecule directly determines.... what?

its function

2

What are the four levels that describe the primary structure of proteins?

The primary structure The secondary structure The tertiary structure The quaternary structure

3

What are proteins?

the most abundant organic molecules in the body and have the widest variety of functions

4

What are proteins used for?

- cell structures and structural body tissues - for controlling chemical reactions - for regulating growth - for defending the body from invaders - catalyze or speed up all reactions occurring in the body - they transport ions and other molecules into and out of the body - can think of them as worker molecules of the body that organize and facilitate all metabolic processes

5

Proteins are organic molecules, what are they made of?

mostly carbon, oxygen, hydrogen, and nitrogen Some contain sulfur, iron, or phosphorus

6

Proteins are organic molecules, what are they made of?

mostly carbon, oxygen, hydrogen, and nitrogen Some contain sulfur, iron, or phosphorus

7

What are the building blocks of protein?

amino acids - linked together

8

What makes each protein unique and defines the function of the protein?

the sequence of the amino acids

9

How many different amino acids are used in the body?

20 and they all share the same basic structure

10

What does the amino acid contain?

- a central carbon atom attached to a hydrogen atom - an amino group (NH₂) - a carboxyl group (COOH) - a unique group of atoms called a side chain designated by the letter R (defines each amino acid) (the side chain can be simple or complex)

11

 

What does the amino acid contain?

 

- a central carbon atom attached to a hydrogen atom - an amino group (NH₂) - a carboxyl group (COOH) - a unique group of atoms called a side chain designated by the letter R (defines each amino acid)

 

12

Amino acids can be linked together in how many combinations to form proteins?

an infinite variety

13

What determines the nature and function of the resultant protein?

the specific combination of amino acids as ordered by the cell's DNA

14

A bond between one amino acids is what type of bond?

a peptide bond Example: a carboxyl group of one amino acid links with the amino group of another amino acid

15

What is a dipeptide bond?

a short chain of two amino acids

16

What is a tripeptide bond?

a chain of three amino acids linked together

17

What is it called when the amino acid chain exceeds 100 amino acids?

a protein

18

What is the secondary structure of a protein?

the natural bend of parts of the peptide chain as it is formed in three dimensions

19

When are the bends stabilized in the secondary structure of a protein?

when the atoms of the protein molecule form weak hydrogen bonds with each other or dehydration synthesis (can be either helical(spiral) or pleated)

20

When are the bends stabilized in the secondary structure of a protein?

when the atoms of the protein molecule form weak hydrogen bonds with each other (can be either helical(spiral) or pleated)

21

What is the tertiary structure?

the overall shape of a single protein molecule

22

What kind of bond occurs when there is a chain of three amino acids linked together?

a tripeptide bond

23

What are structural proteins?

stable, rigid, water-insoluable proteins that are used for adding strength to tissues or cells often call fibrous proteins (because of their long, stringy shape) Examples: collagen - located in the main protein in connective tissues like ligaments, cartilage, bone, and tendons, fibrin, and keatin

24

What are functional proteins?

generally water-soluble and have a flexible, three-dimensional shape, which can change under different circumstances

25

Why are functional proteins called globular proteins?

because they have a convoluted changeable shape

26

What are some examples of Globular proteins?

Hemoglobin, antibodies, protein-based hormones, and enzymes

27

What are the functions of a functional (globular) protein?

chemical reactions, transport of molecules, regulation of metabolism, immune system

28

What is an example of a chemical reaction in a functional (globular) protein?

protein enzymes: essential to almost every biochemical reaction in the body

29

What is an example of a transport of molecules in a functional (globular) protein?

Hemoglobin transports oxygen in the blood

30

What is an example of regulation of metabolism in a functional (globular) protein?

Peptide hormones: regulate metabolic activity, growth, and development. Ex: thyroid hormone regulates metabolic rate and insulin regulates blood sugar levels

31

What is an example of an immune system in a functional (globular) protein?

antibodies (immunoglobulins) are proteins created by immune cells that recognize foreign substances such as viruses

32

What is an example of an immune system in a functional (globular) protein?

antibodies (immunoglobulins) are proteins created by immune cells that recognize foreign substances such as viruses

33

What are the functions of a structural (fibrous) protein?

structural framework and physical movement

34

 

Within the structural framework of a Protein structure, give an example of physical movement.?

 

Actin and Myosin; contractile proteins found in muscles; actin also used for intracellular transport

 

35

Within the structural framework of a Protein structure, give an example of structural framework?

Actin and myosin: contractile proteins found in muscle; actin also used for intracellular transport

36

Functions of proteins

Table 2-3

A image thumb
37

What are enzymes?

essential to the body in their role of catalyzing chemical reactions; speed up a chemical reaction without being distroyed or changed and they are specific to the reaction that they catalyze and to their substrates, which are the substances they act upon.

38

A dipeptide is formed when two amino acids combine by ______________.

Dehydration synthesis

39

The primary structure of proteins consists of .........?

a sequence of amino acids

40

The secondary structure can be either helical or ________ and held by hydrogen bonds between nearby amino and carboxyl groups

pleated

41

What is the quarternary structure of a protein? 

is when two or more protein chains join to form a complex macromolecule

42

What is a disulfide bond?

a covalent bond - is stronger than a hydrogen bond, just an attraction