biological chemistry microbiology – chapter 2. do now what is an atom? what is an element? what is...
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BIOLOGICAL CHEMISTRY
Microbiology – Chapter 2
Do Now
What is an atom?
What is an element?
What is the name of the table that keeps track of all the elements?
Why do biologists study chemistry??
Chemical changes in _________ are essential to all life processes
All _______ ________ are made of the same kinds of matter that make up non-living things
If you learn how ________ in matter occur you will understand the _____ ___________ of organisms
Elements
Elements – ______ _________ that cannot be broken down chemically into simpler kinds of matter
Of more than 100 elements fewer than 30 are important to _______ _______
More than ____% of the mass of living things is composed of combinations of just: _____, ______, _____ and ______
Elements
________ _________ – usually part of the element’s name or the Latin word for the element
Organized into the _______ _______ of elements There are 118 elements, 94 are naturally occurring,
the rest are synthetic (made in particle accelerators) Elements listed by increasing atomic number Columns – groups of elements with similar properties
because of the number of electrons in their outer shell Rows - periods
Atoms – basic units of matter
-________ are the simplest particles of an element that retain all the ________ of that element
-Atoms are so small that their true structure has not been observed
-Models of the atom help us understand their structure enough to _______ how they will act in nature
Atoms
Structure – net electrical charge of _______ a. Protons (charge +) 1 AWU b. neutron (charge 0) 1 AWU c. electrons (charge -) .008 AWU
AWU – atomic weight unit
_________ – central mass of an atom, contains protons and neutrons
Atoms
_________ – high energy particles that move about the nucleus at high speeds in one of several different energy levels
- Electrons in _______ energy levels have more energy than those in ______ energy levels
- Each energy level can only hold a certain _________ of electrons
- 1st energy level can hold ___ electrons
-2nd energy level can hold ___ electrons
- In most elements, the outer energy level is not filled
Atom
Number of Protons?
Atomic number – the number of protons in the nucleus of the atom
Atomic mass – the number of protons plus neutrons in the nucleus of the atom
Isotopes
_________ – A different form of an element which has the same number of protons
and electrons, but has a different number of _________
Carbon (C):-atomic number is 6 - it has 6
protons-mass number is 12 – it has 6
protons and 6 neutrons-C14 – isotope that has 8 neutrons
Hydrogen Isotopes
Isotopes
Radioisotopes – _________ element forms whose nuclei can undergo spontaneous change in which charged particles and radiant energy are released
Atoms Activity
Complete worksheet on atoms
Finish for homework if not completed in class
Do Now
What is the positively charged particle in an atom called?
What is the negatively charged particle in an atom called?
What is the neutral particle in an atom called?
What is an isotope?
Compound
1. A pure substance made up of ____ __ _____ elements combined chemically
2. The properties of compound _______ from the elements it is composed of – H2O vs. H and O
3. The _________ of each kind of element are fixed – Water always H2O
4. Elements combine and form compounds to become more ________
5. Elements are more stable when their outer electron shells are ________
Bonds
Chemical bonds – forces that ____ two or more atoms
a. Covalent bonds – ________ of electrons (water H2O)
b. Ionic bonds – __________ of electrons (sodium chloride NaCl)
Molecules
A _________ is the simplest part of a substance that retains all of the _________ of that substance and that can exist in a ______ state
Hydrogen gas (H2) Water (H2O)
Matter Activity
Complete “Composition of Matter” worksheet.
Finish what you don’t complete for homework.
Do Now
What is a compound?
What is a covalent bond?
What is an ionic bond?
2. INORGANIC CHEMISTRY
STUDY OF COMPOUNDS THAT DO NOT CONTAIN THE THREE ELEMENTS ____, _____, & ____ AT THE SAME TIME.
CAN CONTAIN _____ OF THOSE THREE AND ANY OF OTHER ELEMENTS
ORGANIC CHEMISTRY
LIVING THINGS ________ GREATLY FROM NON-LIVING THINGS
THERE MUST BE A BIG DIFFERENCE IN HOW THEY ARE CONSTRUCTED
THEY ARE ACTUALLY CONSTRUCTED OF THE ________ MATERIALS
THE ONLY DIFFERENCE IS IN HOW THEY ARE ___________
ALL BIOLOGY HAS A __________ BASIS
3. ORGANIC CHEMISTRY
STUDY OF _______ COMPOUNDS - CHEMICAL BASIS FOR LIVING CELLS ALWAYS _____, _____, & ______ SOMETIMES NITROGEN & PHOSPHORUS USUALLY SMALL AMOUNTS OF METALS
THERE ARE “FOUR” DIFFERENT CLASSES OF ORGANIC COMPOUNDS ______________ ______________ ______________ ______________
Carbohydrates
Organic compounds of C, H and O
Used as ________ _________ in cells
Also found in several __________ structures such as bacterial capsules
They are synthesized from water and carbon dioxide during _____________
Carbohydrates
_____________ are the simplest carbohydrates
They are the building blocks for the larger carbohydrates (_______________)
Glucose, galactose and fructose are examples of isomers – they have the same chemical formula C6H12O6
But their structures and properties are different
A. CARBOHYDRATES
Glucose
Represents the basic supply of ______________ in the world
Half of the world’s __________ exists as glucose
GLUCOSE – UNIVERSAL ENERGY
Disaccharides
____________ sugars – composed of _______ monosaccharides held together by covalent bonds
They are made from glucose molecules through ___________ __________– water is removed as the new bonds are formed
Examples are: maltose – found in barley and used to ferment beer lactose – found in milk and digested by bacteria to form
yogurt, sour cream Sucrose – table sugar and is the starting point in wine
fermentation and may be a cause of tooth decay
DISACCHARIDE – TWO MONOSACCHARIDES
Polysaccharides
____________ sugars
Large compounds formed by joining together 100’s or 1000’s of _________ molecules ___________ – used by bacteria as an energy source ___________ – a component of the cell walls of plants
and molds and also used as an energy source by microorganisms
Polysaccharide
Polysaccharides Activity
Complete polysaccharides color worksheet
Finish for homework if not completed in class
Do Now
What are the 4 classes of organic compounds?
What 3 elements are carbohydrates made up of?
What carbohydrate is considered a universal source of energy?
B. LIPIDS
__________ in organic solvents, but not in water
Like carbohydrates, they are composed of C, H, and O, but with much less _________
The best known lipids are ________
Fats are important ___________ energy sources for living things
Fats are also components of ______ ____________
LIPIDS
Fats consist of a 3 carbon ________ molecule and up to 3 long-chain ________ ________
2 major types of fatty acids: ___________ – contain the maximum number of
H atoms ___________ – contain less than the maximum
number of H atoms Unsaturated fatty acids are good for us – they
lower the levels of __________ in the blood
Lipid molecules are sparingly to insoluble in water. Lipids are hydrophobic because the molecules consist of long, 18-22 carbon, hydrocarbon backbones with only a small amount of oxygen containing groups. Lipids serve many functions in organisms. They are the major components of waxes, pigments, steroid hormones, and cell membranes. Fats, steriods, and phospholipids are very important to the functioning of membranes in cells and will be the focus of this tutorial. Fats (triacylglycerols)
LIPIDS
Other types of lipids: ____________ – long chains of fatty acids
Bee’s wax Plant leaves
____________ – contain a phosphate group Cell membranes
____________ – composed of several rings of carbon atoms with side chains Cholesterol Estrogen Testosterone
C. PROTEINS
Most __________ organic compounds of living thingsThey can be:
__________ __________ – regulate the rate of chemical reactions
They are composed of chains of _______ _______
Each amino acid contains Carbon atom Amino group (NH2) Carboxyl group (COOH) Another side group
Amino Acids – there are 20
Proteins
Amino acids are joined together by __________ bonds
The __________ of amino acids is extremely important
One mistake changes the protein (____________)
Protein Structure: Primary – AA sequence Secondary – AA chain twists into a corkscrew pattern Tertiary – Protein folds back upon itself
Proteins
Protein structure animation
D. NUCLEIC ACIDS
Some of the _______ molecules found in organisms ________ – genetic material of the chromosomes that carries
the genetic code ________ – cell messenger that functions in protein
construction
Composed of __________ Carbohydrate molecule (ribose or deoxyribose) Phosphate group Nitrogenous base
DNA – adenine, guanine, cytosine, thymine RNA – adenine, guanine, cytosine, uracil
Nucleic Acids
DNA is located in the ______________ of the cell
It passes on the genetic information and directs _________ synthesis
DNA molecule consists of 2 single strands of DNA in opposite directions arranged in a _________ _______
Nucleic acids can not be altered without disrupting or killing the organism – this can help us control ______________
DNA Structure Animation
Acids and Bases
Degree of ________ or _________ is very important to living systems
You may hear the term pH a lot
What does this mean?
Acids and Bases
Water can dissociate into:
____________ Ions OH-
____________ Ions H3O+
Acids and Bases
- pH is a measure of a solution’s ___________ ion concentration
-pH is a scale of _____ - _____
- an acid = more hydronium ions (H3O+)
- a base = more hydroxide ions (OH-)
Acids and Bases
Acids : Have more hydronium ions Have a ________ taste In concentrated forms can be very ___________
Example:
Strong acid – HCl (hydrochloric acid) Weak acid – CH3COOH (vinegar)
Acid Rain
Acids and Bases
Bases : Have more _________ ions Have a ________ taste Tend to feel _________ because they react with the oil
on our skin to form soap
Example:
Strong base – NaOH (sodium hydroxide) Weak base – NH4 (ammonia)
Acids and Bases
pH scale ranges from 0 – 14:
Solution with a pH of 0 is very __________ Solution with a pH of 14 is very __________ Solution with a pH of 7 is __________ pH can be measured with pH paper or strips
Acid Rain
______ ______is a rain or any other form of precipitation that is unusually _______ (low pH)
It can have _________ effects on plants, aquatic animals, and infrastructure
Acid rain is caused by _________ of compounds of ammonium, carbon, nitrogen, and sulfur which react with the _______ _________in the atmosphere to produce acids
Formation results from both ________ sources (volcanoes, decaying vegetation) and ____________ sources (fossil fuel combustion)
Activity
Complete Acids/Bases worksheet
Finish for homework if not completed in class