Unit 1: Biochemistry
Hypothesis
an explanation that is testable and verifiable for something specific
Theory
a broad framework of explanations based on extensive evidence and testing
Independent variable
a factor that is changed in order to determine its effect on the dependent
Dependent variable
a factor that is measured to determine the effect of the independent variable
Positive control
a group that proves the testing system is functioning and produces an already expected result
Negative control
a group where no change is expected, tests that there are no other affecting factors
Qualitative data
data that is interpretive, observation based
Quantitative data
data that is measurable and countable
Homeostasis
the process of a biological system self regulating itself to maintain stable internal conditions in order to survive
Negative feedback loop
counteracts change in order to put a system back in stable condition
Positive feedback loop
amplifies a change, pushing it to completion
Stimulus
change in the internal or external environment that triggers a change in behavior or physiological response
polar/hydrophilic
water loving
nonpolar/hydrophobic
water hating
adhesion
the attractive force between 2 difference substances
cohesion
the attractive force between the same substances
hydrogen bond
H bonded to O, N, F and is very attracted to lone electrons, strongest IMF
covalent bond
when electrons are shared
electronegativity
how well an atom attracts electrons in a shared chemical bond
heat capacity
how much energy it takes to increase the energy of something
density
how much matter is in a certain volume
pH scale
measures acidity and basicity
solvent
something that dissolves a solute
functional group
a group of atoms attached to a carbon backbone of a molecule that determines its chemical properties and behaviors
monomer
individual molecules that build to make up polymers
polymer
make of monomers, long complex chains
dehydration synthesis
when 2 or more monomers bond together to form a polymer and release a molecule of H2O as a byproduct
hydrolysis
when water is used to break down the bonds of a substance
mono-/di-/polysaccharide
simple units of sugar that cannot be further broken down: glucose, fructose
double sugars that form when monosaccharides are bonded”: sucrose, lactose
long, complex carbohydrates made of chains of monosaccharides used for structural building and energy storage
starch and glycogen for energy storage
chitin and cellulose for building
amino acid
standard building blocks for proteins
polypeptide
chain of amino acids
peptide bond
the covalent bonds between amino acids making up polypeptides
nucleotide
basic structure of DNA and RNA
nucleic acid
large biomolecules for storing genetic information
saturated vs. unsaturated
molecule or solution that is filled/not filled to its max capacity
trans fat
triglyceride
OBJECTIVES:
Ch.1 - Scientific Method & Characteristics of Life
Identify characteristics shared by all living things.
made of one or more cells
can reproduce + pass on their genetic information
requires some form of energy in order to survive
maintains homeostasis
responds and adapts to their environment
Describe an example of how humans maintain homeostasis.
sweating
Compare and contrast negative feedback loops and positive feedback loops. Identify and give examples.
negative feedback loop- counteracts change in order to get things back to normal conditions
homeostasis
positive feedback loop- amplifies change in order to finish it to completion
contractions at birth
Identify or pose a testable question based on an observation, data, or a model.
Determine the null hypothesis and an alternative hypothesis to a scientific question.
null - assumption that there is no effect or change
alternative- assumption that there is a change or relationship between the variables
Explain what a scientific theory is versus a hypothesis.
scientific theories are broader and based on extensive evidence and studies while hypotheses are testable and verifiable by a specific test
Distinguish between qualitative and quantitative data.
one is observable and one is countable
Identify the independent and dependent variables in an experiment.
Determine the control group of an experiment.
Ch.2 - Water & Macromolecules
Understand basic chemistry knowledge:
Understand the relationship between atoms, elements, molecules, and ions.
atoms are the indivisible units of matter
elements are pure substances made of the only one type of atom
molecules are 2 or more bonded atoms
ions are atoms with a charge, imbalance of electrons and protons
Distinguish between a polar and nonpolar molecule.
electrons in polar molecules evenly shared
Explain electronegative, heat capacity, and density.
Explain the pH scale and the difference between acids and bases.
Distinguish between covalent bonds, ionic bonds, and hydrogen bonds.
Diagram and explain the polarity of a water molecule.
Explain and identify the properties of water. Relate them to how water is essential to life on Earth.
Cohesion, adhesion, surface tension, heat capacity, universal solvent, ice floats
cohesion and adhesion allows for capillary action, how water travels from the roots to the branches of a tree
surface tension allows life to life on water
heat capacity allows large bodies of water to absorb heat in the atmosphere in the summers and regulate temperatures
being universal solvent means that water can dissolve a wide range of solutes, allos water to carry oxygen
ice floats so life can still exist below the surface in bodies of water + insulates the bottom of the water
List the five main elements found in living things.
C, H, O, N, P
Explain why organic molecules are based on carbon.
carbon can bond 4 times
Describe the relationship between monomers and polymers.
Explain how polymers are made through dehydration synthesis and broken down via hydrolysis.
in dehydration synthesis, monomers bond to create a polymer through a covalent bond and release a water molecule as a byproduct
hydrolysis requires water in order to overcome the bonds between monomers in polymers
For each of the four main macromolecules:
Identify the monomer(s), polymer(s), main elements, functional groups, and common food sources.
Know the general structure to help you identify examples.
Describe the functions.
Give examples.
Explain the phrase “shape matters” in the context of biomolecules.
the 3D shape determines its biological activity + function
enzymes + active sites
Give examples that relate a molecule’s structure to its function.
Review Questions:
What is the difference between null and alternative hypotheses?
Are teenagers better at geometry than adults? Formulate a null hypothesis and an alternative hypothesis.
there is no difference in age and geometry ability
teenagers are better at geometry
A group of students are interested in examining the potential effects of caffeine (from soda) on heart rate. One group of students hypothesized that soda consumption will not have an effect on heart rate, while another group proposed an alternative hypothesis that soda consumption will increase heart rate. What data would be expected if the alternative hypothesis was supported?
the change in heart rate of someone who drank soda is significantly higher than someone else’s who did not drink soda
How do researchers determine their independent and dependent variables? How are these variables often graphed (i.e. what is on the x-axis and what is on the y-axis)?
IV are changed to determine its effect on the dependent variable
IV is on the x axis and DV is on the y axis
You are washing cars to earn money. For each car you wash you earn $10. Identify the independent and dependent variables.
number of cars washed
money earned
What is the difference between controlled variables and a control group? What is the purpose behind having a control group?
What is the difference between a positive control and a negative control?
positive control: expected to change, determines that equipment is working
negative factors: expected to not change, determines in the testing conditions don’t have any other factors
You want to design an experiment to determine if a new drug has an impact on lowering blood pressure. Test subjects with high blood pressure are given a new medication in pill form. The percentage of patients whose blood pressure decreased is measured. What are good positive and negative controls?
negative: having someone take placebo medicine
positive: using a drug that already is proven to work
What types of data can be collected in an experiment. Give examples of each.
Name the characteristics that all living things have in common.
the ability to reproduce and pass genetic info to their offspring
able to maintain homeostasis
consists of one or more cells
needs energy
responds and adapts to environment
Define homeostasis. Give an example.
the process of a biological system maintaining internal conditions in order to survive changes in environment
Compare and contrast negative and positive feedback loops.
When are negative feedback loops helpful? Give an example of a negative feedback loop.
When are positive feedback loops helpful? Give an example of a positive feedback loop.
Identify the five main elements that make up all living things.
How are hydrogen bonds different from other types of bonds?
IMFs
Draw a few water molecules. Label the types of bonds found in and between the molecules.
How does electronegativity affect the interactions between water molecules?
Describe the properties of water. Give an example of each.
Describe two ways in which the properties of water benefit organisms.
Draw the chemical formula of these functional groups: hydroxyl, carboxyl, carbonyl, phosphate, amine.
How do functional groups affect the structure and behavior of organic molecules?
gives the overall molecule a specific characteristic or behavior that changes its function
What makes carbon a versatile element? Why is it important to living things?
can bond 4 times → creates complex, important biomolecules
Draw an example of a hydrolysis reaction and a dehydration synthesis reaction.
Explain water’s role in hydrolysis and dehydration synthesis reactions.
Draw the general structure of an amino acid.
How do the R groups of amino acids contribute to protein structure?
How does saturation affect fatty acid structure and its behavior?
What is trans fat?
Identify the three components of a nucleotide.
What are three structural differences between a DNA molecule and a RNA molecule?
DNA has a double helix
DNA uses thymine and RNA uses uracil
the base of DNA is deoxyribose vs. RNA’s ribose