Biology ai generated notes
How are the products of producers combined with other elements to form other biological molecules?
Carbon is the molecule of life
Carbon-based molecules are called organic compounds
Almost all the molecules cells make use carbon as the backbone
This is because carbon has four valence electrons, so it can covalently bond with up to four other atoms
This accounts for an enormous variety and possibility of structures
A full electron shell is 8, so atoms are trying to get 8 by adding or losing electrons
Carbon bonds to other carbon in single, double, or triple bonds
Organic compounds are made of carbon chains.
There is great diversity in the structures
These chains can be straight, branched, or ringed
They can vary greatly in length
Functional groups are important parts of a molecule’s function because it is the part of the molecule that participates in chemical reactions.
Sometimes we call them “R” groups for simplicity.
These five functional groups are polar, so they are hydrophilic and dissolve in water.
The methyl group (one carbon and 3 hydrogens, -CH3) is a sixth functional group and is nonpolar (hydrophobic) and isn’t reactive, but DOES affect the molecular shape, and therefore the molecules function.
Female and male hormones, both made from cholesterol, as are all steroids and hormones.
Biological Macromolecules-Carbohydrates, Lipids, Nucleic Acids, Proteins
The main fuel molecules for cellular work
Monomers are monosaccharides - simple sugars
CH2O
Sugars all have: a carbonyl group and hydroxyl groups.
Examples: the structural isomers glucose and fructose, both C6H12O6
Disaccharides
Two monosaccharide monomers joined via a dehydration reaction
Examples: sucrose and lactose
Polysaccharides
Macromolecules, or polymers
Function as storage molecules or structural compounds
Examples (all are polymers of glucose):
Starch - storage molecule in plants
Glycogen - storage molecule in animals
More highly branched than starch
Stored in liver and muscle cells
Cellulose - structural molecule in plants
The most abundant organic compound on Earth
Makes up the cell walls
Chitin - a structural molecule in animals
Composes the exoskeleton of arthropods and cell walls of fungi
Lipids are grouped together because they are hydrophobic,includes fats, oils, phospholipids, waxes, steroids
Fat-Main function is long-term energy storage
Contains twice as much energy as a carbohydrate
A large lipid is made up of a glycerol and three fatty acids (aka trigliceride)
What are the 5 nucleotides-The monomers of nucleic acids are nucleotides
There are five nucleotides
Adenine (the base that makes ATP)
Guanine
Cytosine
Thymine
Uracil
They make two kinds of nucleic acids: DNA and RNA
Each nucleotide has three parts:
A nitrogenous base
A 5-carbon sugar
A phosphate group
These parts form what is called a sugar-phosphate backbone, with the nitrogenous bases sticking out to the side.
ATP is an important energy molecule-It is made of adenine (one of the bases), ribose, and three phosphate groups. The energy released to do work in the cell is stored in the phosphate bonds.
DNA-Deoxyribonucleic acid
It has A, G, C, T
It’s 5-carbon sugar is deoxyribose
It forms a double helix called DNA
DNA carries all the genetic material in a cell
The sides of the helix are “complementary” to each other. More on that later.
The two sides are held together by...you guessed it...HYDROGEN BONDS!
RNA-Ribonucleic acid
It has A, G, C, U
It’s 5-carbon sugar is ribose
It is a single strand
There are three types of RNA in a cell:
Messenger RNA
Transfer RNA
Ribosomal RNA
Proteins-Proteins are the most diverse, both structurally and functionally of all the biological molecules
You are made up of proteins - muscles, ligaments, tendons, collagen, enzymes, antibodies in your immune system - so many more than we could ever hope to learn about!
Enzymes are of particular interest to us in Biology I.
Enzymes act as catalysts…
A catalyst is a substance that speeds up a chemical reaction without being consumed in the reaction itself.
Protein Structure is often a lock-and-key system, many proteins work because they fit exactly on to another protein, or steroid, or other biological molecule.