Biology and Chemistry 6.3 __________________ 6.4 __________________
Jan 14, 2016
Biology and Chemistry
6.3 __________________
6.4 __________________
Water• Water __________________
– ________________________________________________________________________
• Has a _________________________________• These special properties make water act like a
________!• Water helps
_______________________________
Polar Molecules ________________________
Mixtures with water: SOLUTIONS
• Water is considered to be the universal solvent __________________________________________
• A simple solution is _________________________________________
• A solute __________________________________________
• The solvent ___________________________________________
• As a rule of thumb, _______________________________________
Mixtures• Mixture
– A _____________________________________________• Homogenous mixtures
– Is the same throughout the entire mixture– _____________________________________________– Ex: Lemonade (____________________________)
• Heterogeneous mixtures– _____________________________________________– You could pick the pieces apart– Ex: Salad (_________________________________)– Includes COLLOIDS which are kind of strange
• Ex: _____________________________________________
Comprehension Check• Why is water considered the “universal
solvent”?
• Name one common heterogeneous solution.
• Name one common homogeneous solution.
Acids and Bases
• Acids and bases _____________________________________________ _____________________________________________
• Acids– A dissolved substance __________________(hydrogen ion)
– The more H+, ___________________________
• Bases– A dissolved substance ___________________(hydroxide ion)
– The more OH-, _________________________________
pH and Buffers
• pH scale_____________________________________________ ____________________________________________
• Neutral_____________________________________________ _____________________________________________
• Buffers_____________________________________________ Ex: You blood must be at a pH of 7.4, there are buffers in your blood to keep the pH at this range
Oven cleaner
Bleach
Ammonia solution
Soap
Sea water
Human bloodPure waterMilkNormalrainfall
Acid rainTomatojuice
Lemon juice
Stomach acid
NeutralIn
crea
sing
ly B
asic
Incr
easi
ngly
Aci
dic
pH scale
Neutral : equal Neutral : equal amounts of OH- amounts of OH- and H+and H+
Acid: more H+Acid: more H+
Base: more OH-Base: more OH-
Biochemistry Scientists studied Ramshorn snails. Each aquaria contained the same
number of Ramshorn snails, but had differing pH values as shown:Aquaria A – 6.0pH Aquaria B – 10.0pHAquaria C – 12.0pHAfter four months a high percentage of the snails in the aquaria A had
exterior shell damage from dissolving. The snails in aquaria B and C had no shell damage and seemed to be thriving. What was most likely being studied in this experiment?
a. The relationship between pH and the temperature of pond water. b. The effect of predators on the population size of Ramshorn snails. c. The effect of acid rain on the Ramshorn snails. d. The effect of density on the growth of Ramshorn snails.
Testing for pH
• _________: put a drop of the solution on the paper and then compare it to the colors on the key
• ____________
– ____________• Blue paper will turn red in acid (BRA)
– ____________• Red will turn blue in base (BB)
Comprehension Check
• What makes something an acid?
• What makes something a base?
• What are the two testing solutions used when working with pH?
Carbon Carbon Everywhere….• Organic Compounds: these compounds
contain carbon, they are the basis for life (all living things contain carbon)
Examples: Carbs, sugars, fats, proteins, nucleic acids
• Inorganic Compounds: these compounds do not contain carbon
Examples: WATER, Salt, Vitamins,
Carbon Dioxide???
Macromolecule: “giant” molecules found in living cells, they are formed by linking together many smaller units into a larger unit (4 majors ones in all living things!)
Smaller units: monomers(mono=one)
Larger units: polymers(poly=many)
Organic Molecules
Types of Organic Compounds
Carbohydrates
Lipids
Proteins
Nucleic Acids
Comprehension Check
• What do all organic compounds have in common?
• What are the four main types of organic compounds?
Carbohydrates
Monomer: Monosaccharide (Sugar)
Polymer: Disaccharides (Sugar), Polysaccharides (Starch)
Main functions:– Energy– Structure (plants and
arthropods)
Testing for Carbohydrates• Monosaccharide (Sugar)
Benedict’s Test – Add equal parts of the solution
and benedicts– Heat for a few minutes– Bright Colors = Sugar Present
• Polysaccharide (Starch) Iodine Test– Add equal parts of the solution
and iodine– If it turns black/dark purple
there is starch present
Comprehension Check
• What is the other word for sugar?
• What is the other word for starch?
Proteins• Monomer: Amino Acid
– There are 20 types of amino acids, but they all have the same basic structure
• Polymer: Polypeptide • main functions of proteins:
– Build body tissues, nails, hair– Helps reactions in your body occur faster
Test for Protein
• Protein Test Biuret’s Test– Add equal parts solution
and biuret– If the solution turns
lavender then there is protein present
Nucleic AcidsMonomer: Nucleotide
Polymer: DNA, RNA
• Function– Store and transmit
genetic information
Lipids • Monomer: Fatty Acid
• Polymer: Fatty Acid with extended tails
• Insoluble in water!! Why??– Non-polar
• Main functions:
1. Storage of Energy2. Major component of cell
membranes
Examples: fats, oils, waxes, steroids, hormones
Testing for Lipids
• Lipid (Fat) Test Brown Paper Towel Test– Add and few drops of the solution to a BROWN paper towel– Wait for the solution to DRY– If it is transparent there is lipid present