BIO 190- Chapter #3 *The Chemical Basis of Life: Organic Molecules* :)

organic molecules

contain carbon

macromolecules

many molecules bonded together; carbohydrates, lipids, proteins, nucleic acids

what is a key property of the carbon atom

can form 4 covalent bonds (max number of bonds ant atom can make)

what type of bonds does carbon typically form

non polar or polar (depends on electronegativity)

describe hydrocarbons and their relationship with water

non polar molecules containing a carbon backbone that have only C-C and C-H bonds

hydrophobic and poorly soluble in water

what type of carbon bonds would be hydrophilic (more soluble in water)

carbon bonds with more electronegative atoms such as oxygen and nitrogen (more partial negative and partial positive regions)

Describe the length of carbon bonds and it's importantance

the distance between carbon atoms forming a carbon bond is short

shorter bonds=tend to be stronger and more stable, making them more stable with large range of temperatures associated with life.

What is a functional group?

a group of atoms with specific properties that can change the behavior in chemical reactions

ex: ethane is hydrophobic but once -OH is added onto it (a functional group) it will become hydrophillic

What are monomers?

An organic molecule that can be used to form larger molecules, a.k.a. polymer

What are polymers

A large molecule formed by linking many smaller molecules called monomers

Describe a dehydration reaction and how does it affect the polymer

The release of one water molecule as a monomer is added to a chain creating macromolecules

makes the polymer longer

What are hydrolysis reactions?

add H20 back each time a monomer is released, this process breaks down a polymer / makes it shorter

The formation of polymers from monomer typically involves what two things

The removal of a molecule of water and a dehydration reaction

polymers are formed by what reaction type

A dehydration reaction that links monomers in covalent bonds

The reversible process of a dehydration reaction is...

Hydrolysis

what are the 4 major classes of organic molecules

carbohydrates, lipids, proteins, nucleic acids

What are considered macromolecules?

Proteins nucleic acid and some carbohydrates are considered macro molecules because they are composed of many repeating units of smaller building blocks that are linked together

Amino acids are the building blocks for what?

Protein

Describe the defining structure of lipids

lots of carbohydrogem

how do lipids interact with water

non polar/ not soluble

What is the function of proteins?

preform a variety of diverse functions

What two organic molecules are important for storing energy

Carbohydrates and lipids

what are nucleic acids

polymers responsible for the storage, expression and transmission of genetic info

What are carbohydrates?

Organic molecules, composed of carbon and hydrogen and oxygen atoms

What is the functional group in carbohydrates?

Hydroxyl (OH)

What are monosaccharides?

The simplest carbohydrates are the monomers known as monosaccharides

What are the most common types of monosaccharides?

Monosaccharides contain five carbons called pentoses or six carbons called hexoses

what are the most common hexoses(monosaccharides)

Galactose glucose and fructose

What role does glucose play in the cellular activities of living organisms?

Glucose is very water, soluble the circulates in the blood or body fluids of animals where it can be transported across cell membrane. Once inside the cell glucose can be broken down by enzymes into smaller molecules, which then release energy that was stored in its chemical bonds.

Essentially provides an energy source for a variety of cellular processes

What are disaccharides?

A carbohydrate composed of two monosaccharide

What is a glycosidic bond

The bond form between two sugar molecules

Describe energy and matter in regards to

Glucose

The chemical energy stored in the bonds of glucose molecules can be harnessed by living organisms. This energy can be used to perform many functions that support life.

What are polysaccharides?

many monosaccharides linked together to form long polysaccharides

Describe the polysaccharide in living organisms

Starch, glycogen, cellulose, peptidoglycans, chitin, and glycosaminoglycan

Starch and glycogen are used to store what

Energy and cells

Polysaccharide can be hydrolyzed to yield what

To yield monosaccharides which are broken down to provide the energy to make ATP

Describe the structure and function of cellulose

Has a linear arrangement of carbon to carbon bonds and no branching the linear arrangement allows vast numbers of hydrogen bonds to form between cellulose molecules this stack together in sheets to provide strength to plant cell walls

Glucose, galactose, and fructose are examples of what

Hexoses and isomers

how do we use glycogen

its how we store sugar

Are lipids hydrophobic or hydrophilic?

hydrophobic (water fearing)

What is the defining feature of lipids?

They are nonpolar and poorly soluble in water

Name four lipids

Triglyceride, phospholipid, steroids and waxes

Why are lipids not considered to be macromolecules?

Because they are not composed of many monomers in our covalently interconnected

Describe the structure of triglycerides

Consist of a glycerol molecule linked to three fatty acids

Describe a fatty acid chain

A chain of carbon and hydrogen atoms with a carboxyl group at one end

How does a triglyceride form?

Via three dehydration reactions in which fatty acids are bonded to glycerol

Describe saturated fatty acids

When all of the carbons in the hydrocarbon chain form single bonds

Describe unsaturated fatty acids

at least one double bonf between 2 carbons

Describe polyunsaturated fatty acids

Contain two or more carbon to carbon double bonds

Describe the hydrocarbon tail of a fatty acid

Does not form hydrogen bonds with water and is very hydrophobic

Does it take more energy to heat saturated fatty acids or unsaturated?

It requires more heat to melt. saturated fatty acids because they packed together more tightly

Describe triglycerides and their importance for storing energy

The hydrolysis of triglycerides release their fatty acid which metabolize to provide energy to make ATP

What are phospholipids?

Similar to triglycerides, but in a phospholipid, the third OH group of glycerol is linked to a phosphate instead of a fatty acid

What is on the head of the phospholipid? does it interact w water?

The glycerol, backbone phosphate group and charge molecule constitute of a polar head/ interacts w water

Describe the tale of a phospholipid, does it interact w water?

Two fatty acids form nonpolar hydrophobic tails

Since phospholipids have polar and nonpolar region regions, what can you call them?

Amphipathic due to the polar head and non polar tail

Describe steroids structure? relationship with water?

Four fused rings of carbon atoms primarily composed of carbon and hydrogen

usually insolubale in water

Hydrolysis of a triglyceride yields what

One glycerol and three fatty acids

What is the primary structure of a protein?

linear sequence of amino acids encoded by genes

What is secondary structure?

Repetitive folding patterns such as α helix and β pleated sheet

note: in 1 chain u can have various shapes

What is tertiary structure?

3-D shape when all different shapes interact with eachother

often the functional shape

Describe quaternary structure

when 2 polypeptides join to form a functional protein

DNA versus RNA

DNA store, genetic information coded in the sequence of their building box. RNA are involved in decoding the information into instructions for linking a specific sequence of amino acids to form a polypeptide.

DNA and RNA are polymers consisting of linear sequences of repeating monomer each monomer is known as what

Nucleotides

Name the three components of a nucleotide

1. A phosphate group,

2. a pentose sugar (deoxyribose or ribose)

3.nitrogenous base

hang ten appearance

What is dioxyribose?

A five carbon sugar found in DNA

Name the different nucleotides present in DNA and their rings

Purine bases: Adenine, guanine= fused double rings

"purse as gold"

Pyrimidine bases: cytosine, thymine = 1 ring

Describe a double helix

Two strands of DNA hydrogen bonded with each other

name the base pairs in RNA

A + U, C + G

uracil replaces thymine

cell wall of plants

cellulose

energy storage in plants

starch

energy storage in animals

glycogen

Exoskeleton of insects and crustaceans and the cell wall of fungi

chitin

A chain of carbon and hydrogen atoms with a carboxyl group at one end is called a

fatty acid

name the common steroids

Estrogen

Cholesterol

Androgens

quaternary structure

two or more interacting polypeptides

how would you identify a monosaccharide

by a carbon ring and one oxygen

how can monosaccharides be joined together

by a dehydration reaction to form disaccharides

disaccharides can be broken down through _____ reactions

hydrolysis

monosaccarides and disaccharides often function as ....

an energy source

carbs often end in what

-ose

what are the 2 classes of nucleic acids

DNA and RNA

ON exam !!! How do you visually tell the difference between RNA ans DNA

look in bottom corner

RNA has OH attached to the monosaccaride whereas DNA has H attahced to the monosaccaride

what are proteins composed of

polymers composed of 20 different amino acids

how are amino acids categorized

by the chemical properties in their side chains (some R groups are polar some are not)

how can you tell if an amino acid is non polar

if you only see carbon and hydrogen in its side chain it is non polar/hydrophobic

how can you tell if an amino acid is polar

has something other than carbon at the end of its side chain

(like OH or NH2 or SH)

describe a monounsaturated fatty acid

1 double carbon bond (kink shape)