|
Life science biochemistry notes
Organic Compounds
•Organic compounds contain carbon atoms and are found in
living things.
••Most inorganic compounds do not contain carbon atoms.
. carbon dioxide and carbon monoxide are not organic compounds.
••Carbon atoms can readily form four covalent bonds with other atoms
including other carbon atoms. The carbon bonds allow the carbon atoms
to form a wide variety of simple and complex organic
compounds.
Write the structural formula for acetic acid (pg. 28)
Write the chemical formula for acetic acid
Write the structural formula for glucose (pg. 30)
•••Large Carbon Molecules- Macromolecules
Carbohydrates
•Carbohydrates are organic compounds composed of carbon, hydrogen,
and oxygen in a ratio of about one carbon to two hydrogen atoms to
one oxygen atom.
••Carbohydrates are a source of energy and are used as structural
materials in organisms.
••Monosaccharides
–Carbohydrates are made up of monomers called monosaccharides.
••••Disaccharides and Polysaccharides–Two monosaccharides join to
form a double sugar called a disaccharide.
–A complex sugar, or polysaccharide, is made of three or more
monosaccharides.
Draw a disaccharide
Draw a polysaccharide (glycogen, pg. 30)
•Proteins
•Proteins are organic compounds composed mainly of carbon, hydrogen,
oxygen, and nitrogen.
••Proteins have many functions including structural, defensive, and
catalytic roles.
•Amino Acids–Proteins are made up of monomers called amino acids.
The sequence of amino acids determines a protein’s shape and
function.
•Dipeptides and Polypeptides–Two amino acids are joined by peptide
bonds to form a dipeptide.–A long chain of amino acids is called a
polypeptide.
Draw an amino acid (Cysteine pg. 32)
What is a peptide bond?
•Enzymes are protein catalysts that are essential to life.
–Enzymes speed up chemical reactions and bind to specific
substrates.
–The binding of a substrate with an enzyme causes a change in the
enzyme’s shape and reduces the activation energy of the reaction.
Draw an Enzyme-substrate reaction (will be discussed in class)
Lipids
•Lipids are nonpolar molecules that store energy and are an important
part of cell membranes.
••Fatty Acids
–Most lipids contain fatty acids, long chain of carbon molecules that
have a hydrophilic end (water loving), and a hydrophobic (water
hating) end.
•Triglycerides
–Triglycerides consist of three fatty acids and one molecule of
glycerol.
Write the chemical structure for a Triglyceride (pg. 31)
Fats can be saturated or unsaturated
Saturated fats have no double bonds in the fatty acid chain.
Saturated fats are solid at temperature.
Diets high in Saturated fats may result in heart disease.
Give Six examples of saturated fats
Unsaturated fats have double bonds in the fatty acid chain.
Unsaturated fats are liquid at room temperature.
Give Six examples of unsaturated fats
•Phospholipids
–Phospholipids, which make up cell membranes, consist of two fatty
acids and one glycerol molecule.
•Waxes
–A wax is made of one long fatty acid chain joined to one long
alcohol.
–•Steroids–A steroid is composed of four fused carbon rings.
Give examples of how waxes are produced by living things.
Nucleic Acids
•A nucleic acid is a large and complex organic molecule that stores
and transports information.
•The nucleic acid deoxyribonucleic acid (DNA) contains genetic
information for cell activities.
••Ribonucleic acid (RNA) molecules play many key roles in building of
proteins and can act as enzymes.
Draw a DNA molecule
Intro to Bio and Ecology Review Questions
Chapter 1 and !4
Define:
Biology
Ecology
Genes
Homeostasis
Cell
Hypothesis
Theory
Prediction
Experimentation
Food web
Food chain
Community
Biome
Producers
Consumers
Decomposers
plankton
Nitrogen cycle
Nitrogen is a component of ____________?
Water cycle
Carbon cycle
Know the major characteristics of all of the biomes
Amount of precipitation
Type of vegetation
Average yearly temperature range
CH 1-2 THEMES IN BIOLOGY
•Unity in the Diversity of Life–Life is so diverse,or full of
variety.
Yet, life is also characterized by unity, or features that all living
things have in common.
–••–The tree of life shows that all living things have descended with
modification from a single common ancestor. Yet, there are many
different lineages, or branches, representing different species. ••
Interdependence of Organisms
•Organisms live in interdependent communities and interact with both
organisms and the environment.
Evolution of Life
•Evolution, or descent with modification, is the process in which the
inherited characteristics within populations change over generations.
••Evolution helps to explain how species came to exist, have changed
over time, and adapt to their environment.
•Natural Selection–Natural selection is a process by which organisms
that have certain favorable traits are better able to survive and
reproduce successfully than organisms that lack these traits.
–Natural selection can lead to the evolution of populations.••
CH 1-3 Science as a Process
•Steps of the Scientific Method–The scientific method involves making
observations, asking questions, forming hypotheses, making
predictions, designing experiments, analyzing data, and drawing
conclusions.••
Scientific Processes
•Collecting observations
•Asking questions
•Forming hypotheses and making predictions
•Confirming predictions (with experiments when needed)
•Drawing conclusions
Observing and Asking Questions
•The process of science begins with an observation.
••An observation is the act of perceiving a natural occurrence that
causes someone to pose a question.
•••Forming a Hypothesis
•hypothesis is a proposed explanation for the way a particular aspect
of the natural world functions.
••Predicting–To test a hypothesis, scientists make a prediction that
logically follows from the hypothesis. ••••••
•Performing the Experiment–A controlled experiment compares an
experimental group and a control group and only has one variable. •••
•Performing the Experiment–The experimenter manipulates the
independent variable.
–The experimenter measures the dependent variable because it is is
affected by the independent variable. ••
•Testing the Experiment–Experiments should be conducted without bias
and they should be repeated. ••
•Analyzing and Comparing Data–Scientists analyze data to draw
conclusions about the experiment performed.••
Drawing Conclusions
•Making Inferences–An inference is a conclusion made on the basis of
facts and previous knowledge rather than on direct observations. ••
•Applying Results and Building Models–Scientists often apply their
findings about the natural world to solve practical problems. ••
Constructing a Theory
•A theory is a set of related hypotheses confirmed to be true many
times, and it can explain a great amount of data.••
Communicating Ideas
•Publishing a Paper–Scientists submit research papers to scientific
journals for publication.
–In peer review, the editors of a journal will send submitted papers
out to experts in the field who anonymously read and critique the
paper.
••
Honesty and Bias
•Communication between scientists about their methods and results
helps prevent dishonesty and bias in science.•••
•Conflict of Interest–The threat of a potential scandal based on
misleading data or conclusions is a powerful force in science that
helps keep scientists honest and fair.•• |
