Lecture 6 - Biomolecules Part 2 Flashcards
What are proteins?
Large, complex molecules that do most of the work in cells
required for structure, function, and regulation of the body’s tissues and organs
Amino Acids
What proteins are made up of
How many types of amino acids are there that can be combined to make a protein?
20
Essential Amino Acids
Cannot be made in the body
Semi-Essential Amino Acids
Arginine and Histidine
Can be synthesized by adults but not kids
How are amino acids linked to form proteins?
Carboxyl and amino groups are synthesized through dehydration synthesis. Resulting compound has peptide bonds
Proteins shape is determined by:
The order that amino acids are joined in
Shape determines function
Dipeptide
2 amino acids linked by a peptide bond
Polypeptide
Many amino acids linked by peptide bonds
Protein structure:
One or more ploypeptides folded into a specific 3-dimensional shape
4 Levels of Protein Structure
Primary Structure
Secondary Structure
Tertiary Structure
Quaternary Structure
Primary Structure
Unique Sequence
Secondary Sequence
Hydrogen bonds between amino acids in the polypeptide
Parts of polypeptide coil or fold into a local pattern
Two types of secondary structures
Alpha Helix & Pleated Sheet
Tertiary Structure
Overall 3-dimensional shape of a folded polypeptide
Quaternary Structure
Only in proteins with two or more polypeptides
Overall shape after polypeptides fit together
Lysozyme
Antimicrobial enzyme produced by animals that forms part of the innate immune system
Define Sickle Cell Hemoglobin
Sickled red blood cells are stiff and angular, causing them to become stuck in small capillaries
Denaturation of Proteins
Process in which 3-dimensional shape of polypeptide becomes distorted
Protein no longer functions
Causes of Denaturation
Temperature
PH
Salts
Protein Functions
- Enzymatic
- Structural
- Contractile
- Defensive
- Transport
- Signaling
Protein functions: Enzymes
Enzymes speed up chemical reactions
Protein functions: Structural Proteins
Collagen - makes up bones, tendons, ligaments, skin
Keratin - Makes up hair, nails, claws, hooves, reptile scales
Protein functions: Contractile proteins
Mediate sliding of contractile fibers (Muscles)
The two most important contractile proteins are called
Actin & Myosin
Protein functions: Defensive Proteins
fight off infections
Protein functions: Transport Proteins
act as doors to the cell
Protein functions: Signaling
interacts with and affects the behavior of neighboring cells
Two types of nucleic acids:
DNA
RNA
DNA
Molecule that contains every organism’s unique genes.
Nucleic acids are monomers or polymers?
Polymers
The monomers of nucleic acids are:
Nucleotides
The main difference between DNA and RNA nucleotides is:
Sugar
RNA - Ribose
DNA - Deoxyribose
Polynucleotides
Combination of nucleotide monomers which are connected through covalent bonds
DNA is _____ stranded
Double
RNA is ______ stranded
Single
Types of RNA involved in protein synthesis:
mRNA
tRNA
rRNA
mRNA:
messenger RNA, carries DNA message to ribosomes
tRNA:
Transfer RNA, transfers amino acids to ribosomes
rRNA:
Ribosomal RNA, makes up ribosome-protein factories of the cell
