Biology B1.2- proteins

What is a polypeptide

A protein

What is the general structure of animo acids

What is the R group in the structure of animo acids

variable group, changes every time

what is the carboxyl group

What do 2 amino acids make

Dipeptide + water

What does an amino acid and sulfur make

Disulfide bond

What is between the 2 amino acids

Peptide bond

How many different amino acids are there

20

Where are amino acids made

On a ribosome

How many amino acids can humans make

11

What are the sources of amino acids

Meat

Beans

What are genes

The code fir the sequences of animo acids

Describe fibrous proteins

• Provides structure and support to cells and tissues

• Collagen - skin, tendons, ligaments

• Keratin- hair, nails, claws

• long structural shape

• insoluble in water

• made up of repeated sequences of amino acids

Describe globular proteins

• All enzymes - All amino acids

• Eg. Hemoglobin

• Do the things in the body - metabolic

• tightly coiled

• soluble in water

Denaturation definition

Breaking the bonds that hold a protein in shape

Proteins can be denatured by heat and a change in pH

genome definition

every complete set of genetic material in an organism and every organism has its own unique DNA

proteone definition

every organism has its own unique proteins

describe amino acids

• some are hydrophobic and fold inwards

• some are hydrophilic and connect with water which creates a hydrogen bond

• when in a solution, they change it

  • some are ionized

what happens to the change of properties of the R groups

it gives rise to various bonds and the “folding” of polypeptides

does hydrophobic fold in or out

fold in

does hydrophilic fold in or out

fold out

describe primary structures

• basic order of animo acids

• in the linear polypeptide protein chain

• coded by genes

• joined by peptide bonds

• first step

• DNA informs the primary structure

what are the bonds in a primary structure

only polypeptide bonds

describe secondary structure

• 2nd level of folding

• either forms of alpha helix or beta - pleated sheet

  • forms regular reapeating intervals

what structure are fibrous proteins

secondary level

what are the bonds in secondary structures

• polypeptides

  • hydrogen

describe tertiary structure

• 3D protein shape

• results from the folding of the polypeptide

• sulfur is in the R group

  • hydrophobic fold inside since they dont like getting wet

what are the bonds in tertiary structure

• hydrogen

• disulfide

• ionic

• polypeptide

describe a disulphide bond

2 adjacent cyteine amino acids which have sulfur in the R group forming a covalent bond- leading to a folding in the chain

describe tertiary structure

• not every protein gets to this level

• only globular proteins get to this or tertiary level

• combination of different polypeptide chains joined together

  • includes all level structures

what are the bonds in quaternary structure

• ionic

• polypeptide

• disulfide

  • hydrogen

describe non conjugated quaternary structures

quaternary structure without a prosthetic group

describe a prostheic group

• non protein molecules

  • has 2 alpha and 2 beta chains with a Heme group (contains ions)

what are conjugated quaternary structure

quaternary structure with prosthetic group

organisation of globular proteins

tertiary or quaternary structure

organization of fibrous proteins

secondary structure

Describe collagen quaternary structure

Secondary structure

String and stretchy but short

Building tissues that hold the body together

Fibrous proteins with polypeptide chains

Repeating sequence = regular collagen shape

Describe insulin non conjugated structure

Short genes in the human goenum

Protein hormone

describe hemoglobin conjugated structure

Large protein

Function is to reversibly to O2 in the lungs

what is the order of the structures

Primary → secondary → tertiary→ quaternary