Quiz 2 - Biochem (Carb, Lip, NA) Flashcards
what are the 4 major classes of macromolecules
- Carbohydrates
- Lipids
- Proteins
- Nucleic Acids
What are Macromolecules?
Larger molecules that are formed by smaller ones that joined together
What are Polymers?
Long molecules are built by linking repeated building blocks in a chain. Joined by cov bonds
What are monomers?
building blocks, repeated small units
-joined by cov bonds to make polymers
How do you build a polymer?
-DEHYDRATION SYNTHESIS REACTION
What happens in a DSR? (dehydr..)
-Joins monomers by “taking” out H2O
-One donates OH, other H.
-requires energy & enzymes
How do you break down a polymer?
-Digestions Hydrolysis Reactions
What are carbohydrates composed of, function, and monomer involved
- C, H, O
- Fast energy
- Energy storage
- Raw materials
- Structural Materials
- SUGARS (starch, cellulose)
Explain DHR (dig hydrolysis reac)
-Use H2O to break polymer (reverse DSR)
-Requires enzymes
-RELEASES energy
How are sugars classified? Explain the classifications
Classified by # of carbons.
6C = hexose (glucose)
5C = pentose (ribose)
3C = triose (glyceraldehyde)
What are the 2 functions of polysaccharides?
-ENERGY STORAGE
-starch (plants)
-glycogen (animals) in liver n muscles
-STRUCTURE
- cellulose (plant)
-chitin (arthropods n fungi)
What happens to the energy store in C-C bonds?
Harvested in cellular respiration
Explain why starch is easy to digest but cellulose is not? (humans)
Starch: all glycosidic linkages are on same side = molecule lies flat
Cellulose: cross linking between OH (H-bonds) = rigid structure
What is the covalent bond called that disaccharides create?
A glycosidic Linkage
What sugar structure form rings?
5C & 6C (ribose, glucose)
Give three points explaining cellulose
-Most abundant organic compound on earth
-herbis have evolved a mechanism to digest cellulose, most carnis have not
CELLULOSE = undigestible roughage
What are monosaccharides, and give an example
- Simple 1 monomer sugars
-Glucose
What are the 3 types of sugars?
-Monosaccharides
-Disaccharides
-Polysaccharides
What are polysaccharides, and give an example
-Large polymers
-Starch
What are disaccharides, and give an example
- 2 monomers
-Sucrose
What is the diff between linear and branched polysaccharides? give examples
LINEAR: slow release
- Starch (plant)
BRANCHED: fast release
-Glycogen (animal)
Branched has faster digestion
What the diff between alpha and beta glucose?
ALPHA: H on top, OH on bottom
BETA: OH on top, H on bottom
Why do branched polysaccharides digest easier?
Many branches means many ends that enzymes can digest at.
How can herbivores digest cellulose so well?
BACTERIA live in their digestive systmes & help digest cellulose-rich (grass) meals
What are the properties of lipids? (5)
-Hydrophobic
-Consist mostly of hydrocarbons
-Not true macromolecules (too small)
-Not true polymers (not composed of repeating monomers)
- Varied in form and function
What are the four biologically important lipids
1) Fats
2) Phospholipids
3) Steroids
4) Waxes
How are fats assembled and composed of
-Dehydration Synth reac
-Composed of glycerol and fatty acids
What is the structure of glycerol
-Alcohol w/ 3 carbons, each with a hydroxyl group attached
Give a description of fatty acids (3 points)
- Long carbon skeleton - 16 to 18 C in length
- Ends in carboxyl group
- Non-polar C-H bonds make it hydrophobic
What are the two types of fatty acids?
-Saturated (single bonds, hydrogen
- Unsaturated (double bonds, not sat w/ H)
Which type of acid is kinked and why?
Unsaturated fatty acid. This is due to presence of cis double bond
Triglyceride is made up of what?
Glycerol + 3 fatty acids
Explain triglycerides in adipose tissue
-Adipose tissue is composed of cells that store fat in the form of triglycerides
-related to caloric intake compared to burn
-trig stored in adipose can be broken down by hydrolysis; cellular respiration
-insoluble in water
Explain adipose tissue in animals
-Animals in cold regions have thick layers of adipose called blubber between skin n muscle
- “endotherms” - animals that use homeostasis)
Give 4 points on saturated fats and an example
-No double bonds in fatty acid chains
-Can pack tightly together
-Solids at room temperature due to high melting point
-Linked to atherosclerosis
-EX: butter
Give 4 points on unsaturated fats and an example
-Double bond in one or more chain
-Kinks in chain due to cis double bonds
-Cant pack together tightly
-Liquids at room temp
-EX: VEGETABLE OILS
What is the difference between a monounsaturated and polyunsaturated fatty acid?
Mono = 1 double bond
Poly = more than 1
what is the difference between cis and trans fatty acids?
CIS: hydrogen atoms are on same side of the 2 carbons that r double bonded
TRANS: opposite sides
Give 4 points of trans fats
- Most unhealthy fat
- Increases risk of heart disease
-Produced by industrially adding H to liquid plant oils to make more solid (margarine)
-UnSAT fats w/ 1+ double bonds in “trans” config
What disease is often correlated with trans fats?
Coronary heart disease. Diseased arteries were found to contain high amts of trans fats.
What are the 3 functions of fats
1) ENERGY STORAGE - 1 gram of fat store 2x more energy than 1 gram of carbohydrate - stored in adipose cells
2) CUSHIONS VITAL ORGANS
3) INSULATES THE BODY - maintains body temp
What are phospholipids made of
Glycerol + 2 fatty acids + phosphate group
What is it called with something is part hydrophobic + philic?
Amphipathic
What is the structure of phospholipids?
- Phosphate head
- Glycerol backbone
- Fatty acid tails
WHat is the phospholipid syimbol
composed of a philic head and phobic tails, will self-assemble into bilayer structures when add to water
What are cell membranes made of
Phospholipid bilayers
Give 4 points on steroids
-Carbon skeleton consists of 4 fused rings
-Non-polar due to large # of C-H. hydrophobic
-Occur naturally in plants, animals, fungi
-Variation in functional groups attached
Name 3 steroids and their structure
-Cholesterol
-Testosterone
-Estrogen
-ALL RINGS
What is GOOD cholesterol
-high density lipoprotein; reduces deposition of cholesterol in plaques on blood vessel walls
What is BAD cholesterol
LDL (low dens lipoprotein) - increased deposition of cholesterol in plaques
what is the significance of “like dissolves like” with steroids and membranes?
Steroid hormones can pass through the cell and nuclear membrane of target cells; can then regulate expression of genes in DNA to ctrl protein prod.
Give 3 points of explain waxes
-Cover feathers of some aquatic birds
-Cover surfaces of leaves to prevent water loss
-Composed of long fatty acid chains connected to alcohols
What do Nucleic Acids do?
in charge of the storage and transmission of hereditary info
What are the 2 types of nucleic acids
-Deoxyribonucleic Acid (DNA)
-Ribonucleic acid (RNA)
Explain the central dogma of biology
DNA is the “code” of life that determines the protein sequence which is the “stuff” of life
If nucleic acids = polymers, what do monomers equal?
Nucleotides
What are the 3 parts of nucleotides
-nitrogenous base (C-N ring); A,T,C,G in DNA- A,U,C,G in RNA
-pentose sugar (5C) ; ribose in RNA, deoxyribose in DNA
-Phosphate group
What are the 2 types of nitrogenous bases
-Purines; double ring N base, adenine, guanine
-Pryimidines; single ring N base; cystosine (C), thymine in dna, uracil in rna
Explain the nucleic acid structure (4)
-Backbone; suger to PO4 bond
-DSR
-phosphodiester bond (covalent)
-polymer grows in one direction
-nitrogenous bases hang off the sugar-phos backbone
explain the dna molecule (and one point on RNA)
-Double helix
-H-bonds between bases join 2 strands
-easy to ‘unzip’
RNA: single stranded
how do the pairings of nucleotides work?
purine bonds with pyrimidine (A ::T)
How is DNA copied?
-Replication
-Complementary strands in DNA
When does a cell copy DNA
-Cell rep (mitosis)
-Gamete production (meiosis)
Who figured out the DNA model
-Watson n crick
-Wilkins
-Rosalind Franklin
