Unit 3: Biochemistry

Question 1

whaWhat are the 4 most important types of organic compounds?

Answer 1

carbohydrates, lipids, proteins, and nucleotides.

Question 2

How many electrons does carbon have in the valence shell?

Answer 2

4 and the octet rules dictates that atoms tend to react in a way to complete their valence shell with 8 electrons.

Question 3

How do carbon atoms complete their valence shells?

Answer 3

sharing electrons via covalent bonds, not by accepting or donating electrons.

Question 4

Carbon atoms often share with ____ forming a long ____.

Answer 4

carbon atoms often share with other carbon atoms forming a long carbon skeleton.

Question 5

Carbon and hydrogen groupings are called?

Answer 5

hydrocarbons: an organic compound consisting entirely of carbon and hydrogen.

Question 6

What is a functional group?

Answer 6

group of atoms linked by strong covalent bonds and tend to function in chemical reactions as a single unit. they are unlikely to be parted.

Question 7

What are the 5 functional groups important in human physiology?

Answer 7

hydroxyl, carboxyl, amino, methyl, and phosphate groups.

Question 8

What is a macromolecule?

Answer 8

a large molecule formed by covalent bonding: carbohydrates, lipids, proteins, and nucleic acids.

Question 9

Some macromolecules are made up of several copies of single units called?

Answer 9

monomers: a molecule that can react with other similar monomers to form a polymer. EX: AMINO ACIDS COMBINING TO FORM PROTEINS.

Question 10

monomers polymers dehydration synthesis hydrolysis?

Answer 10

monomers form polymers via dehydration synthesis and polymers are split into monomers via hydrolysis.

Question 11

What is a carbohydrate?

Answer 11

a molecule composed of carbon, hydrogen, and oxygen. They also contain several HYDROXYL groups which makes them POLAR by nature.

Question 12

What is a saccharide?

Answer 12

saccharide is another name for carbohydrate and it means sugars. There are 3 forms that are important in the body: monosaccharides, disaccharides, and polysaccharides.

Question 13

Monosaccharides?

Answer 13

A monosaccharide is a monomer of carbohydrates.
HEXOSE SUGARS: contain 6 carbon atoms: glucose, fructose, galactose.
PENTOSE SUGARS: contain 5 carbon atoms:
ribose and deoxyribose

Question 14

Disaccharides?

Answer 14

Disaccharides are formed via dehydration synthesis and it is a pair of monosaccharides(2). The bond is called a glycosidic bond.
Example: Sucrose, lactose, maltose. The body does not use these directly and are split into monosaccharides via hydrolysis in the digestive tract.

Question 15

Polysaccharides?

Answer 15

Polysaccharides contain a few to a thousand monosaccharides.
- Starch: polymers of glucose. they occur in long chains called amylose or branched chains called amylopectin. EASY TO DIGEST IN PLANT BASED FOODS.
- Glycogen: polymers of glucose. stored in the tissues of animals. the human body stores excess glucose as glycogen.
- Cellulose: polysaccharide made of glucose that is the primary component of the cell wall in plants. it is not digestible but helps u feel full and promotes healthy digestive tract. also reduces risk of heart disease and cancer.

Question 16

Pentose sugars are a critical component of __ and ___

Answer 16

atp and the nucleotides that make up DNA and RNA.

Question 17

glucose and fructose make?

Answer 17

sucrose

Question 18

galactose and glucose make?

Answer 18

lactose

Question 19

glucose and glucose make?

Answer 19

maltose

Question 20

What is a lipid?

Answer 20

lipids are a type of organic compound made up mostly of hydrocarbons. The nonpolar hydrocarbons make lipids hydrophobic. When mixed into liquids, they form an emulsion not a solution.

Question 21

What is the most common dietary lipid group and explain it.

Answer 21

triglycerides and is found mostly in body tissues. this is often referred to as a “fat”.
- It is made up of a glycerol backbone and 3 fatty acid chains.

Question 22

What does a glycerol backbone consist of?

Answer 22

3 carbon atoms and each of them are bonded to a hydroxyl group.

Question 23

What does a fatty acid chain consist of?

Answer 23

long chain of hydrocarbons with a carboxyl group and methyl group at opposite ends extending from each of the carbons of the glycerol.

Question 24

Saturated fatty acids?

Answer 24

fatty acid chains that have no double carbon bonds. they are solid or semi solid at room temp. butter is an example.

Question 25

unsaturated fatty acids?

Answer 25

one double carbon bond and kinked at that bond. liquid at room temperature.

Question 26

What are triglycerides good for?

Answer 26

- major fuel source for the body. - fuel long physical activity. - assists with absorption of vitamins. - cushions boes and organs Fatty acids are also components of GLYCOLIPIDS in cell membrane.

Question 27

polyunsaturated fatty acids?

Answer 27

contain two or more double carbon bonds, liquid at room temperature.

Question 28

What is a phospholipid?

Answer 28

amphipathic lipid molecule containing a phosphate head and two fatty acid tails and a glycerol backbone. It is the major molecule comprising plasma membranes.

Question 29

Hydrophilic vs hydrophobic?

Answer 29

hydrophilic: water loving/water soluble/polar hydrophobic: water fearing/not soluble in water/nonpolar phospholipid head is hydrophilic but the tails are hydrophobic.

Question 30

Steroid?

Answer 30

A steroid compound aka sterol has 4 hydrocarbon rings bonded to other atoms. The sterol that makes the most important contribution to humans is cholesterol.

Question 31

What is cholesterol important for?

Answer 31

bole acids, emulsify dietary fats, building block of many hormones.

Question 32

What are proteins?

Answer 32

proteins are organic molecules composed of amino acids linked by peptide bonds.

Question 33

Proteins in the body are and found where?

Answer 33

important components of all tissues and organs. - protein include keratin in epidermis of skin. - collagen in the dermis of the skin. - in bones. - in meninges that cover brain and spinal cord.

Question 34

What makes proteins different from carbohydrates and lipids?

Answer 34

carbs and lipids are composed of hydrocarbons and oxygen, but all proteins contain NITROGEN and many contain sulfur.

Question 35

What distinguishes the 20 amino acids from one another?

Answer 35

variable group which is also referred to as the side chain or R group. it can be polar or nonpolar giving each amino acid unique characteristics.

Question 36

Proteins are polymers of nitrogen containing monomers called?

Answer 36

amino acids. an amino acid is a molecule composed of amino group, carboxyl group, and side chain, hydrogen atom.

Question 37

The bonding holding amino acids together is called a?

Answer 37

peptide bond which is a type of covalent bond occurring between amino acids.

Question 38

Peptide vs polypeptide?

Answer 38

peptide is a short chain of amino acids and strands with less than 100 amino acids are polypeptides instead of proteins.

Question 39

Primary structure of protein?

Answer 39

straight and linear line.

Question 40

Secondary structure of protein?

Answer 40

alpha helix or pleated sheet.

Question 41

Tertiary structure of protein?

Answer 41

3 dimensional shape.

Question 42

Quaternary structure?

Answer 42

polypeptide subunits can be identical or different. for example: hemoglobin is composed of 4 tertiary polypeptides, two are called alpha chains and two are beta chains.

Question 43

Functions of proteins? READ TEXTBOOK MORE FOR THIS ONE!!!!!

Answer 43

- movement - muscle contraction - intracellular transport - structural framework for mechanical support - catalytic action/chemical reactions - transporting molecules - regulate fluid pH - regulate metabolism - defend body - can be used for energy

Question 44

Nucleotides?

Answer 44

a nucleotide is a class of organic compounds composed of: - phosphate group - pentose sugar - nitrogenous base

Question 45

Nucleotides can be assembled into?

Answer 45

nucleic acids(DNA/RNA) or adenosine triphosphate(ATP).

Question 46

Adenosine triphosphate ATP?

Answer 46

composed of ribose sugar, adenine base, 3 phosphate groups. - It is classified as a high energy compound because the covalent bonds linking the 3 phosphate groups store a LOT of potential energy

Question 47

When a phosphate group leaves ATP it is called?

Answer 47

adenosine diphosphate, and removing yet another leaves adenosine monophosphate.

Question 48

What is phosphorylation?

Answer 48

addition of a phosphate group to an organic compound.

Question 49

Deoxyribonucleic acid vs ribonucleic acid?

Answer 49

DNA is a nucleotide that stores genetic information. It contains deoxyribose, phosphate group, and one nitrogen base. RNA helps manifest genetic code as protein. It contains ribose, phosphate group, and one nitrogen base.

Question 50

What are the bases for DNA?

Answer 50

adenine, guanine, cytosine, and thymine.

Question 51

What are the bases for RNA?

Answer 51

adenine, cytosine, guanine, and uracil.

Question 52

How many genes do humans have?

Answer 52

around 22000!

Question 53

Chromosomes?

Answer 53

A long DNA molecule that contains a number of genes. 23 pairs=46 chromosomes. These genes carry the genetic code to build ones body and they are unique for each individual except identical twins.

Question 54

mRNA?

Answer 54

messenger RNA is created during protein synthesis to carry genetic instructions from the DNA to the ribosomes.