understanding life substances ORGANIC COMPOUNDS understanding life substances

Elements in Life To put it simply, all life contains the same basic materials. Living organisms are made up of the following elements with the following percentages:

O2 CO2 CH4 C6H12O6 H2O Elements in Life How do we know if something is living? It contains the elements C and H together. We call this organic. Inorganic molecules do NOT contain carbon and hydrogen together. O2 CH4 CO2 C6H12O6 H2O

Elements in Life Water! Our bodies are 65% water, but water is inorganic Organic molecules can be broken down into 4 main categories. These substances are needed for life to grow and function properly. Proteins Carbohydrates Lipids Nucleic Acids

How Do We Get These ORGANIC Molecules? We eat to take in these substances. Food for building materials - proteins to make more of us (cells) for growth for repair Food to make energy - carbs calories to make ATP Plants don’t need to eat to get these molecules. They make them! Does anyone know HOW?

Breaking Down and Building Up How does the food turn into molecules that run and build our body? The food gets broken down into simple units. Then those units are used or assembled in our bodies and turn into something we need!

Monomers and Polymers We call the building blocks monomers:    The complex units are called polymers:                                                

Breaking it Down The food we eat gets broken down into simple units (monomers). We call this process digestion. We can break it down physically We can break it down chemically

+ + + + + + water water water water water = = = = Hydrolysis Literally means “water – cutting”. Water is used to break down various polymers. + + + + + + water water water water water = = = =

Starch is digested to Glucose Example of Digestion ATP ATP ATP ATP ATP ATP starch glucose ATP Starch is digested to Glucose

Building it Up Once we have these monomers in our bodies, we use them for various functions. Synthesis building bigger molecules from smaller molecules building cells & bodies repair growth reproduction

Dehydration Synthesis Dehydration = lose water Synthesis = put together - water =

amino acids = building block Example of Synthesis amino acids protein Proteins are synthesized by bonding amino acids amino acids = building block protein = polymer

Life Substances Now we’ll be talking about these life substances in detail. Remember, all living things contain these substances. Our bodies contain them, and the food we eat contains them too…this makes sense since the food we eat comes from living material as well.

Life Substances in Detail Usually ends in... Monomer Polymer Elements it Contains Indicator Chemical Structure What it Does Food Examples Examples in Our Bodies Unique Properties Protein Carbo-hydrate Lipid Nucleic Acid

PROTEINS Monomer/Polymer Usually ends in –in, or –ine. Monomer – Amino Acids 20 different kinds of amino acids Polymers – Protein, Peptide, Polypeptide PROTEINS amino acid amino acid amino acid amino acid amino acid – – – –

PROTEINS About Proteins How many amino acids are linked together to make this protein? Is this a dipeptide of a polypeptide? PROTEINS

PROTEINS Elements/Indicator Elements: C, H, O. N Indicator: Biuret solution PROTEINS DID YOU KNOW? It’s the Nitrogen in proteins that make our urine YELLOW? The more N, the greater the color…

PROTEINS Chemical Structure The function of a protein depends on its SHAPE. Proteins fold into different shapes because of certain bonds in the amino acids. Different shape = different function! PROTEINS growth hormone hemoglobin pepsin

It’s SHAPE that matters! Proteins do their jobs, because of their shape Unfolding a protein destroys its shape wrong shape = can’t do its job unfolding proteins = “denature” temperature pH (acidity) PROTEINS unfolded “denatured” folded

PROTEINS What it Does What do proteins do? many, many functions hormones signals from one body system to another insulin movement muscle immune system protect against germs enzymes help chemical reactions PROTEINS

Examples in Food/Bodies Body Examples muscle skin, hair, fingernails, claws collagen, keratin pepsin digestive enzyme in stomach insulin hormone that controls blood sugar levels Food Examples - meat - beans - egg - cheese PROTEINS

CARBOHYDRATES Monomer/Polymer Usually ends in –ose Monomer = simple sugar, monosaccharide Polymer = carbohydrate, polysaccharide CARBOHYDRATES sugar sugar sugar sugar sugar sugar sugar sugar

CARBOHYDRATES About Carbohydrates Looking at the molecules below, identify the: Monosaccharide (glucose) Disaccharide Polysaccharide CARBOHYDRATES sugar sugar DISACCHARIDE sugar MONOSACCHARIDE sugar sugar sugar sugar POLYSACCHARIDE

CARBOHYDRATES Elements/Indicator Elements: C, H, O Indicator: Glucose – Benedicts Solution Starch – Iodine CARBOHYDRATES

CARBOHYDRATES Chemical Structure Monosaccharides have a simple ring structure. When they are bonded in a chain they make a polysaccharide. CARBOHYDRATES

CARBOHYDRATES What it Does Function: - quick energy from simple sugars, like fruits   - energy storage from complex carbs, like starch - structure cell wall in plants CARBOHYDRATES

What it Does CARBOHYDRATES

Examples in Food/Bodies Body Examples Glycogen Glucose Cellulose (plants only) Food Examples Bread Fruit Veggies Ice Cream CARBOHYDRATES Plants need cellulose! When we eat it, we can’t digest it.

Digesting Starch vs. Cellulose enzyme starch easy to digest Animals do not have the enzyme to digest cellulose. We need the help of bacteria living in our intestines. enzyme cellulose hard to digest

CARBOHYDRATES Cellulose Cell walls in plants herbivores can digest cellulose well most carnivores cannot digest cellulose that’s why they eat meat to get their energy & nutrients cellulose = roughage stays undigested keeps material moving in your intestines CARBOHYDRATES Cross-linking between polysaccharide chains = rigid & hard to digest The digestion of cellulose governs the life strategy of herbivores. Either you do it really well and you’re a cow or an elephant or a horse (spend a long time digesting a lot of food with a little help from some microbes & have to walk around slowly for a long time carrying a lot of food in your stomach) Or you do it inefficiently and have to supplement your diet with simple sugars, like fruit and nectar, and you’re a gorilla.

Different Diets of Herbivores Cow can digest cellulose well; no need to eat other sugars Gorilla can’t digest cellulose well; must add another sugar source, like fruit to diet

CARBOHYDRATES Helpful bacteria How can cows digest cellulose so well? BACTERIA live in their stomachs & help digest cellulose-rich (grass) meals CARBOHYDRATES Eeeew… Chewing cud?

http://www.youtube.com/watch?v=_qf_r5EVP6U

LIPIDS Monomer/Polymer Don’t end in anything specific Monomer = fatty acid Polymer = Lipid LIPIDS

LIPIDS Elements/Indicator Elements: C, H, O Indicator: Brown Paper Towel LIPIDS

LIPIDS Chemical Structure Very long chains. Made up of a “head” and “tail” Hydrophobic “water-hating” tail Hydrophilic “water-loving” head LIPIDS

LIPIDS What it Does Function: energy storage cell membrane very concentrated twice the energy as carbohydrates! cell membrane cushions organs insulates body think whale blubber! LIPIDS

Examples in Food/Bodies Body Examples - Hormones - Sex Hormones - estrogen - testosterone Food Examples Fats Oils Waxes LIPIDS

LIPIDS Saturated fats Most animal fats Limit the amount in your diet solid at room temperature Limit the amount in your diet contributes to heart disease deposits in arteries LIPIDS

LIPIDS Unsaturated fats Plant, vegetable & fish fats liquid at room temperature the fat molecules don’t stack tightly together Better choice in your diet LIPIDS

Saturated vs. Unsaturated  LIPIDS

Other Lipids in Biology Cholesterol good molecule in cell membranes make hormones from it including sex hormones but too much cholesterol in blood may lead to heart disease LIPIDS

Other Lipids in Biology Cell membranes are made out of lipids phospholipids heads are on the outside touching water “like” water tails are on inside away from water “scared” of water forms a barrier between the cell & the outside LIPIDS

http://www.youtube.com/watch?v=NmcLCpXVTrY

NUCLEIC ACIDS Monomer/Polymer Ends in –ine or –cil Monomer = Nucleotide Polymer = Nucleic Acid NUCLEIC ACIDS nucleotide – nucleotide – nucleotide – nucleotide

NUCLEIC ACIDS Elements/Indicator Elements: C, H, O, N, P, S Indicator: Everything has DNA, but if we wanted to compare DNA we can use Gel Electrophoresis. NUCLEIC ACIDS

NUCLEIC ACIDS Chemical Structure Double strand twists into a double helix weak bonds between nitrogen bases join the 2 strands A pairs with T A :: T C pairs with G C :: G the two strands can separate when our cells need to make copies of it NUCLEIC ACIDS

NUCLEIC ACIDS What it Does Function: genetic material stores information genes blueprint for building proteins DNA  RNA  proteins transfers information blueprint for new cells blueprint for next generation DNA NUCLEIC ACIDS proteins

NUCLEIC ACIDS Examples in Organisms Examples in Organisms: DNA RNA DeoxyriboNucleic Acid RNA RiboNucleic Acid NUCLEIC ACIDS

NUCLEIC ACIDS Copying DNA Replication copy DNA 2 strands of DNA helix are complementary they are matching have one, can build other have one, can rebuild the whole NUCLEIC ACIDS when cells divide, they must duplicate DNA exactly for the new “daughter” cells Why is this a good system?

Newly copied strands of DNA DNA Replication Copying DNA pairing of the bases allows each strand to serve as a pattern for a new strand NUCLEIC ACIDS Newly copied strands of DNA The greatest understatement in biology!

http://www.youtube.com/watch?v=xZaMi6OhsSU