Cell Biology Lecture 4

Front 1

Secondary structure development begins when?

Back 1

Secondary structure occurs immediately as we begin to fold into primary structure, occurs in the cell during protein synthesis.

Front 2

Secondary structure consists of what two forms?

Back 2

beta sheet and alpha helix

Front 3

Beta sheet

Back 3

. Very stable. Folding, interaction of oxygen’s and hydrogen’s giving hydrogen bonding. R groups are doing nothing, just point in or out of board

Front 4

What is the difference between beta sheet and alpha helix?

Back 4

Some amino acids are more important in b-sheet and some more important in alpha helix.

Front 5

In beta sheets and alpha helix's amino acid R groups are?

Back 5

hydrophobic

Front 6

Tertiary structure

Back 6

o Considered final structure of any single peptide. The 3D structure. Can include secondary structure as part of tertiary

Front 7

What is difference between secondary structure and tertiary structure?

Back 7

 In secondary, bonding was hydrogen and peptide bonding.
 In tertiary, get bonding dealing with R group bonding (along with hydrogen and peptide bonding). R groups interact and form weak bonds, ionic bonds, etc. In occasion R groups will interact with other R groups in covalent bonds.

Front 8

What is the maximum size of a tertiary structure?

Back 8

150 amino acids

Front 9

When tertiary structure reaches the maximum size, what is it called?

Back 9

a domain

Front 10

Domain

Back 10

Domains increase flexibility. Kooks and crannies in domains are important as binding sites (later). Domains have functional consequences in cell.

Front 11

Cysteine

Back 11

Has sulfur associated with its R group. Will link and form a disulfur bond. Only ones that usually have cysteine bonds are those that function outside of the cell (are exported).

Front 12

Quarternary structure

Back 12

Have one or more peptides interacting. Refer to individual peptides as monomers.

Front 13

If a quarternary structure has 2 peptides interacting, what is it called?

Back 13

A dimer

Front 14

If a quarternary structure has 3 peptides interacting, what is it called?

Back 14

A trimer

Front 15

If a quarternary structure has 8 peptides interacting, what is it called?

Back 15

An octomer

Front 16

If a dimer, if one peptide is different from the other, what is it called?

Back 16

A heterodimer

Front 17

If two identical monomers are linked together, forming a dimer, what is it called?

Back 17

A homodimer

Front 18

Actin

Back 18

 Actin is a single monomer. In muscles, actin is composed of multiple monomers of actin linked together, two chains which twist together.

Front 19

Viruses are often coated in?

Back 19

polymers of protein. Protein coat is lots of linked monomers. In many polymers, no energy is required to form. Form by self assembly.