Download topics covered during the fall semester ecology

TOPICS COVERED DURING THE FALL SEMESTER
ECOLOGY
1. Levels of organization—p.21
2. FOOD TYPES:
A. Producers, Autotrophs
B. Consumers, Heterotrophs
C. Herbivores, Carnivores, Omnivores, Detritivores, Decomposers
D. Chemosynthetic Organisms—p. 68
3. Feeding Relationships:
A. Trophic Levels, Energy Pyramids (Energy, Biomass, Numbers—pp. 72-73)
B. Competition, Predation, Symbiosis (mutualism, commensalism, parasitism—p. 9293)
4. 10% rule
5. Remember that energy is lost from trophic level to trophic level since it is lost as
organisms use it for cell processes (feeding, getting rid of wastes, growing, etc.) and
heat.
6.
7. Remember the “Producers” are the FIRST trophic level, the “Primary Consumers” are
the SECOND trophic level, the “Secondary Consumers” are the THIRD trophic level, and
the “Tertiary Consumers” are the FOURTH trophic level.
8. Matter, unlike energy, can be RECYCLED. Water, Carbon, Nitrogen, and Phosphorus are
recycled through organisms, land, water, and the atmosphere. (p. 74-79). When a
nutrient is scarce (not much is available) or cycles slowly, it is called a limiting nutrient.
When an aquatic ecosystem gets a large amount of a limiting nutrient, the result is often
an immediate increase in the amount of algae and other producers. The result is called
an algal bloom.
9. Know the following terms: Abiotic factors, biotic factors, niche, habitat, population
density, immigration, emigration, exponential growth, and logistic growth, and carrying
capacity. Again, an ecosystem’s population growth can be limited by Densitydependent factors such as competition, predation, parasitism, and disease. DensityIndependent factors also affect all populations. These factors are unusual weather,
natural disasters, seasonal cycles, and certain human activities such as damming rivers
and clear-cutting forests.
10. Renewable resources are those that can be regrown if they are alive or re-supplied by
biochemical cycles if they are abiotic. An example is a forest. Non-renewable resources
are those that cannot renewed once they are used. An example is fossil fuel.
11. Ecosystems are constantly changing in response to natural and human disturbances.
The changes that happen to a community over time are known as ecological succession.
These changes can be slow or sudden. Primary succession occurs on land where no soil
exists. The first species to populate the area is called a pioneer species and is normally
a lichen. (p. 94) Secondary succession is a disturbance of some kind in an existing
community without removing the soil. Fires and farming are examples. (p. 95)
12. Carrying Capacity is largest number of individual organisms that a given environment
can support.
BIOMOLECULES
1. Atoms—protons, neutrons, protons
2. Chemical Bonds—covalent bonds, ionic bonds, hydrogen bonds
3. Polarity—unequal distribution of electrons on a water molecule leads to zones of
negative and positive charges. (The “ears” or hydrogen atoms are usually negative
because their electrons are traveling around the “face” or oxygen atom which is positive
because it “keeps” the electrons from the hydrogen atom.)
a. Cohesion is attraction between molecules of the same substance. Water is
extremely cohesive because the “ears” of the molecule attract the “face” of
another water molecule.
b. Adhesion is attraction between molecules of different substances. The meniscus
formed by water in a test tube is an example.
4. Solutions are made by adding a solute (like sugar or salt) to a solvent (normally water.)
a. Isotonic solutions are those in which the solute is an equal amount to the
solvent.
b. Hypertonic solutions are those in which the solute is in higher concentration
than the solvent. (more salt or sugar than water.)
c. Hyptonic solutions are those in which the solute is in lesser concentration than
the solvent. (more water than sugar or salt.)
5. pH Scale—Indicates how many H+ ions or OH- ions are in a solution. Acids have H+ ions
and are located on the pH scale from numbers 0 – 6. Bases have more OH- ions than
acids and are located on the pH scale from numbers 8 – 14. The number 7 is considered
to be neutral. (p. 43)
6. There are 4 large biomolecules that are found in all living organisms. These are also
called macromolecules.
a. CARBOHYDRATES/SACCHARIDES:
i. Monomer: Glucose
ii. Polymer: Starch
iii. Function: Provide energy
iv. CHO
b. LIPIDS:
i. Do not have a monomer. The “backbone” is glycerol
ii. The major part of the lipid is the fatty acid.
iii. Function: Store energy, cell membranes, and waterproof coverings.
iv. CH—remember cokes and hamburgers make a fatty acid!
v. One fatty acid=Monoglyceride (one “string”)
Two fatty acids=Diglyceride (two “strings”)
Three fatty acids=Triglyceride (three “strings”)
c. NUCLEIC ACIDS:
i. Two kinds: DNA and RNA
ii. Monomer: Nucleotide (Phosphate Group, Deoxyribose sugar, and
nitrogenous base like adenine, thymine, guanine, and cystosine.
iii. Function: Store and transmit heredity or genetic information and make
proteins from the code/order of the bases on the DNA molecule.
iv. CHNOP
d. PROTEIN:
i. Monomer: Amino Acid
ii. Polymer: Polypeptide or protein
iii. Function: Each protein has a specific role.
1. Structures like muscle and bones
2. Enzymes—control the rate of chemical reactions
3. Regulate cell processes like digesting food
4. Transport substances into and out of cells
5. Help fight disease
iv. Can have four shapes—like a crumpled ball
****Remember that polymers are made from monomers (Polymerization is the name of the
process). To make the monomers “stick” or bond together, water has to be REMOVED from the
two molecules (H+ from one molecule and OH- from the other molecule.) This is called
DEHYDRATION SYNTHESIS. To break the bonds between the monomers that form the
polymer, we ADD water. This process is called HYDROLYSIS.
7. Activation Energy is the energy that is needed to get a reaction started. Enzymes speed
up chemical reactions that take place in the cell. Enzymes LOWER THE ACTIVATION
ENERGY.
8. Enzymes are not used up, but they can wear out. The body will replace them when they
do. The activity/action of enzymes can be affected by temperature, pH, and the
concentration of both the enzyme and the substrate (the “thing” being acted upon by
the enzyme.) Enzymes can be identified as they end in the suffix –ase. For ex: lactase.
9. The ACTIVE SITE is the place where the substrate is placed on the enzyme. (Look at your
handout.)
CELL STRUCTURES AND FUNCTIONS
1 .Prokaryotes—one celled. DNA floats in the cytoplasm. Bacteria are the only organism. Some
live in extreme environments like mud, volcanic vents, intestines of animals.
2. Eukaryotes—All other organisms. Can be one celled or multi-celled. Has the DNA located in
a membrane bound nucleus. All other organelles have membranes.
3. Cell Theory—p. 170
4. Cell Structures and Functions—p.174-182
5. Cell Membranes and Diffusion—p.182-189
A. Diffusion, Osmosis
B. No Energy required to move particles—Facilitated Diffusion
C. Energy required—Active Transport (Endocystosis such as Phagocytosis and
Pinocytosis. Exocytosis.)
PHOTOSYNTHESIS AND CELLULAR RESPIRATION Know your chemical formulas. Look
at the power points and page 206 for photosynthesis. Look at page 222 for cellular respiration.
Remember that the products recycled between photosynthesis and respiration are oxygen,
carbon dioxide, and water.
1. Purpose of Photosynthesis: Make Glucose to be used by all organisms, including the
plants.
2. Purpose of Respiration: Make ATP molecules from glucose.
3. ATP molecules are easily used by organisms as compared to glucose.
4. Energy is stored between the bonds of phosphate. As the ATP is used, it becomes ADP
and AMP.
5. Photosynthesis occurs in the chloroplasts of plants. Cellular respiration occurs in the
mitochondria of both plants and animals.
6. Most of the time cellular respiration occurs in the presence of oxygen. Sometimes, the
oxygen cannot be present because it will kill the organism or because the organism
cannot get the oxygen to the cell fast enough. This leads to a process called
fermentation. There are two kinds: alcoholic fermentation—yeasts and lactic acid
fermentation—body muscles.
7. The wastes products of cellular respiration are carbon dioxide and water.
8. One molecule of glucose = 36 ATPs.
CELLULAR GROWTH AND DIVISION
1. Cell cycle – Chpt. 10, p. 240 – 252.
2. 3 reasons why cell cycle occurs---Look at review sheet given to you last week in class or
the website.
3. 3 parts to the cell cycle—Interphase, M phase, Cytokinesis.
4. 3 parts to Interphase—G1, S, G2
5. Parts of M phase—Prophase, Metaphse, Anaphase, Telophase
6. During the S phase the chromosomes must REPLICATE. That means they chromosomes
must make copies of themselves.
7. REPLICATION : Involves 3 enzymes.
a. Helicase -- Breaks the hydrogen bonds between the nitrogenous bases
b. DNA Polymerase—Brings the correct nucleotide to the “exposed” nitrogenous
base. Adenine must bond to Thymine. Cytosine must bond to Guanine. The
DNA Polymerase also “spell checks” the placement to make sure the correct
nitrogenous bases are in place.
c. Ligase—bonds the phosphate/sugar “handles” to the new phosphate/sugar
handles.
8. Each of the replicated chromosomes will have one original strand and one new,
COMPLIMENTARY STRAND.