Metabolism - 1 Flashcards
Macromolecules
Definition:
Large molecules necessary for life that are built from smaller organic molecules.
Macromolecules
What are the 4 main macromolecules?
- Carbohydrates
- Proteins
- Lipids
- Nucleic Acids
What macromolecules can be broken down easily through hydrolysis?
- carbohydrates
- proteins
- nucleic acids
What are lipids broken down by?
Lipolysis
What is hydrolysis?
Adding water to a molecule to breaking a bond
What are the simplest macromolecules?
Carbohydrates
What are carbohydrates made up of?
Carbon backbone attached to a 2:1 hydrogen to oxygen ratio
What are carbohydrates used for?
Used as fuel or converted to other macromolecules
What are the main types of carbohydrates?
- monosaccharides (1)
- disaccharides (2)
- polysaccharides (many)
What are the monosaccharides?
- glucose
- fructose
- galactose
What are the disaccharides?
- maltose
- sucrose
- lactose
What are the complex (many sugars)?
- starch
- glycogen
- fiber (cellulose)
- chitin
Definition:
Monosaccharides
Simple sugars that can not be broken down by hydrolysis into smaller carbohydrate molecules
What carbohydrates can be readily used as fuel sources in the body?
Monosaccharides
What is a dietary monosaccharide?
A monosaccharide that are readily absorbed by the small intestine
What monosaccharide is always in a disaccharide?
Glucose
What % of calories consumed in the USA diet come from sucrose?
25%
Where is lactose found naturally?
milk and milk sugar products
What is the least sweek of the 3 main dietary disaccharides?
lactose
Can polysaccharides be branched or unbranched?
Yes
What is starch?
Storage form of carbohydrates in plants
What are the 2 starchs?
- amylose (long, straight chains that are twisted to form helical coils that are slow to breakdown)
- amylopectin ( highly branched glucose chains that are fast to breakdown)
Definition:
Storage form of carbohydrates in animals (mainly in muscle and liver)
Glycogen
Is glycogen highly branched?
Yes - therefore fast to breakdown
How do we convert glucose in the body?
Via glycogenolysis
What is the most abundant naturally occuring polysaccharide?
Cellulose
Definition
Found in plant walls and provides structural support to the cell
cellulose
How many amino acids are there?
20
Protein function depends on…
it’s shape
What causes sickel cell anemia?
A change in 1 amino acid which causes abnormnal folding of protein
Sickled cells are unable to fit in capillaries, reducing gas exchange abilities and may put person at higher risk for forming clots
Definition:
Enzyme
proteins that catalyze biomechanical reactions
What are enzymes essential for?
Chemical processes like digestion and cellular metabolism
What are the 2 main types of enzymes? What do they do?
Anabolic: build
Catabolic: break down
What does amylase do?
Digestion of carbohydrates in mouth and SI
What does pepsin do?
Digestion of proteins in the stomach
What does lipase do?
Emulsifies fats in SI
What does trypsin do?
Further digestion of proteins in SI
Why can you take a pills for lactose intolerance, but not for insulin?
You stomach won’t digest the enzyme that breaks down lactose, but your stomach will break down insulin
Definition:
Proteins secreted by endocrine cells and act to control or regulate specific physiological processes like growth, development, metabolism, reproduction
Hormones
Definition:
Protein hormone that helps regulate blood glucose levels.
Insulin
T/F: some proteins act as receptors to detect the concentrations of chemicals and send signals to respond
true
What hormones are examples lipid steroids?
estrogen and testosterone
Definition:
Fats, oils, waxes and other similar compunds in our bodies
Lipids
What are lipids mainly made from?
Carbon, hydrogen and oxygen
T/F: vast majority of lipids are polar (don’t dissolve in water)
false, most are non-polar
How are lipids transported?
Lipoproteins
What are the main uses of lipids?
Energy storage and structure
What are the 3 main types of lipids?
- fats
- phospholipids
- steroids
Fats are constructed from…
a single glycerol molecule and three fatty acids
Definition:
Fatty acids with the maximal number of hydrogen atoms possible for the structure with no double bonds. Form straight chains.
saturated fatty acids
Definition
Unsaturated fatty acids
Has one or more double bonds present and forms a bent chain
Are saturated or unsaturated fatty acids solid at room temp?
saturated
What type of lipid is a major component of the plasma membrane?
Phospholipid
What differentiates phospholipids from fats?
Instead of 3 fatty acids attached to a glycerol backbone, they have 2 fatty acids also attached to a glycerol backbone but with a phosphate group
T/F: The phosphate group on phospholipids is negatively charged making it non-polar and hydrophobic
False
It is polar and hydrophillic (water loving)
Are fatty acid tails hydrophobic or hydrophilic?
Hydrophobic, non-polar (water fearing)
Do water-soluble or fat-soluble molecules pass right through the phospholipid bilayer?
Fat-soluble, water soluble water molecules need a trasnporter
Steroids play a role in…
reproducion, absorption, metabolism regulation, and brain activity
What is the structure of steroids?
4 linked carbon rings
T/F: steroids are soluble in water
false, insoluble in water (hydrophobic)
Definition:
Most common steroid mainly synthesized in the liver.
cholesterol
What is cholesterol the precursor to?
- vitamin D
- steroid hormones like estrogen, progesteron, testosterone
- plays a role in synthesizing aldosterone (used for water retention)
- contributes to the formation of cortisol which plays a role in metabolism
What are th 2 main types of nucleic acids?
DNA and RNA
Definition:
The gentic material of organisms.
DNA
Definition:
Instructions for protein sythesis.
RNA
