Semester 1 Study Guide (covers Chapter 2,3,10,13, & 14) Name KEY Per:____
Evolution- Chapter 10:
Define: Hypothesis: an educated guess
Theory: an explanation that explains multiple phenomena that has been tested by many scientists and proven correct
Natural Selection: mechanism by which individuals that have inherited beneficial traits produce more offspring than average.
Species: a group of organisms so similar to one another and can breed and produce fertile offspring
Evolution: change in a species over time
Fitness: measure of an organism’s ability to survive and produce offspring
Artificial Selection: process by which humans modify a species by breeding it for certain traits
List and describe the 4 Principals of Darwin’s Theory of Evolution
1. Variation- differences in physical traits of an individual from the group to which it belongs.
2. Overproduction- producing more offspring than can possibly survive.
3. Adaptation- certain variations allow an individual to survive better than other individuals it competes against.
Descent with modification- natural selection results in species with adaptation that are well suited for survival and reproduction in their environment.
Types of Isolation (Define and give example):
Geographic: isolation between populations due to physical barriers.
Ex: two species of shrimp are isolated by the Pacific Ocean.
Reproductive: occurs when members of different populations can no longer mate with one another. It is the final step in becoming two different species.
Ex: two tropical fruit flies no longer mate
IF TWO ORGANISMS CANNOT MATE AND PRODUCE A FERTILE OFFSPRING THEN THEY ARE TWO DIFFERENT SPECIES. TWO DIFFERENT SPECIES CANNOT MATE AND MAKE A NEW SPECIES.
Which of these best illustrates natural selection?
A. An organism with favorable genetic variations will tend to survive and breed successfully.
B. A population monopolizes all of the resources in its habitat, forcing other species to migrate.
C. A community whose members work together utilizes all existing resources and migratory routes.
D. The largest organisms in a species receive the only breeding opportunities.
A species of finch has been studied on one of the geographically isolated Galapagos Islands for many years. Since the island is small, the lineage of every bird for several generations is known. This allows a family tree of each bird to be developed. Some family groups have survived and others have died out. The groups that survive probably have
A. interbred with other species. C. inherited some advantageous variations.
B. found new places on the island to live. D. been attacked by more predators.
A single species of squirrel evolved over time into two species, each on opposite sides of the Grand Canyon. This change was most likely due to
A. higher mutation rates on one side. C. low genetic diversity in the initial population.
B. the isolation of the two groups. D. differences in reproductive rates.
Define the following terms and give examples:
Homologous structures: body part that is similar in structure on different organisms but perform different functions.
Example: forelimb of mammals
Analogous structures: body parts that are different in structure on different organisms but have a similar function.
Example: wings on a bird and butterfly
Vestigial structure: remnants of an organ or structure that functioned in an earlier ancestor.
Example: human appendix
What are the lines of evidence that Darwin used to support his argument for evolution? Biochemistry, Fossils, Homologous Structures, Embryology, Mimicry/Camouflage.
Ecology- Chapter 13
Community Interactions & Ecological Succession- Chapter 14:
Define: Biodiversity: variety of life within an area
HOT Question: Why is biodiversity important to an ecosystem?
Biodiversity helps keep an ecosystem healthy and functioning. A high degree of biodiversity allows an ecosystem to be stable.
Autotroph: organism that obtains its energy from abiotic sources such as sunlight
Heterotroph: organism that obtains its energy and nutrients by consuming other organisms.
Biomass: total dry mass of all organisms in a given area.
Immigration: movement of individuals into a population.
Emigration: movement of individuals out of a population.
Carrying Capacity: number of individuals that the resources of an environment can normally and persistently support.
Invasive species: a species that outcompetes an existing species for its niche.
HOT Question: Describe what would happen if the population exceeded the ecosystems carrying capacity: The population would die off until the population was below the carrying capacity due to limited resources.
HOT Question: Describe the effect on an invasive species on an ecosystem: it outcompetes native species and decreases biodiversity of an area.
SYMBIOSIS / Meaning / ExampleMutualism / Ecological relationship between two species in which each species benefits. / Bees and flowers
Parasitism / Ecological relationship in which one organism benefits and the other is harmed. / Tick on a dog
Commensalism / Ecological relationship in which one species benefits and the other is not affected in any way. / Bacteria on our skin
Nitrogen: 78% of our air is made up of this and it’s unusable: nitrogen gas
What organism converts N2 gas into a usable form? bacteria
What is the process called: nitrogen fixation
Carbon: What process removed carbon from the atmosphere? Photosynthesis
Name 2 processes that return carbon to the atmosphere: respiration, fires
Communities: Identify whether each item is a biotic or abiotic factor by placing a check mark in the appropriate box.
Item / Average temp. / pH of soil / Concentration of CO2 / Number of prey / Precipitation / Invasive speciesBiotic / X / X
Abiotic / X / X / X / X
Trophic Level Chart:
Trophic Level / Autotroph or heterotroph / Consumer or Producer / Example / What it eats: omnivore, herbivore, carnivore, makes own food / Calculate the amount of energy transferred to each level1st / Autotroph / Producer / Algae / Makes its own food / 25,000 kcal
2nd / Heterotroph / Consumer / Shrimp / Herbivore / 2,500 kcal
3rd / Heterotroph / Consumer / Bass / Omnivore / 250 kcal
4th / Heterotroph / Consumer / Seal / Carnivore / 25
Which way does energy flow in an Energy Pyramid? (UP or DOWN) UP
What is the main difference between primary and secondary succession? Secondary succession already has grass formed so it happens faster.
Scientists found that, over a period of 200 years, a mountain pond was transformed into a meadow. During that time, several communities of organisms were replaced by different communities. Which of these best explains why new communities were able to replace older communities?
A. The original species became extinct. C. Species in the older community died from old age.
B. The abiotic characteristics of the habitat changed. D. Diseases that killed the older organisms disappeared.
Rabbits introduced into Australia over 100 years ago have become a serious pest to farmers. Rabbit populations increased so much that they displaced many native species of plant eaters. What is the most logical explanation for their increased numbers?
A. Rabbits have a high death rate. C. There are few effective predators.
B. Additional rabbit species have been introduced. D. There is an increase in rabbit competitors.
Complete burning of plant material returns carbon primarily to the
A. herbivores. B. water. C. vegetation. D. atmosphere.
Which of these organisms would most likely be found at the top of an energy pyramid?
A. clams B. sardines C. sharks D. kelp
Biochemistry (Macromolecules and Enzymes)- Chapter 2:
Define: Polymer: large, carbon-based molecule formed by monomers.
List the 4 macromolecules and complete the chart:
Macromolecule / Monomer / Function / ExamplesProtein / Amino Acids / Helps with eyesight, movement, and digestion / Meat, seafood, eggs, hair, nails
Carbohydrates / Monosaccharaides / Energy storage / Grain, pasta, sugar
Lipids / Glycerol + 3 Fatty Acids / Energy storage, membranes, insulation / Cholesterol, fat, wax
Nucleic Acid / Nucleotides / Genetic code for protein production / RNA, DNA
Polymers are made up of many monomers.
Enzymes are a type of proteins which macromolecule). Their job is to increase/decrease the speed of a chemical reaction by raising/lowering the activation energy required. Enzymes are reusable which means when they finish breaking up one bond, they can move to the next. The three things that can slow down or stop an enzyme are pH, temperature, and concentration.
Describe and draw the lock and key model of enzymes (there are 3 steps):
Cells & Membranes- Chapter 3:
Describe the characteristics:
Prokaryote: cell that does not have a nucleus or other membrane-bound organelles.
Eukaryote: cell that has a nucleus and other membrane-bound organelles.
Organelles: Describe the structure & function of the following organelles:
Nucleus: dense organelle present in eukaryotic cells that contain the genetic material for the cell.
Endoplasmic Reticulum: organelle involved in protein and lipid synthesis that has ribosomes attached to the outside.
Ribosomes: a tiny particle that consists of RNA and proteins that are found in the cytoplasm of the cell that synthesize polypeptides.
Golgi Apparatus: a complex of vesicles and membranes within the cytoplasm that is involved in secretion and transport.
Chloroplasts: contains chlorophyll and is where photosynthesis occurs.
Mitochondria: powerhouse of the cell the supplies it with energy.
Cell Wall: rigid layer that supplies structure.
Cytoplasm: the material within a living cell.
Describe the characteristics cell membrane (what is it made of, how many layers, what is its function)
Phospholipid bilayer that helps protect the cells from the outside world.
What does semi-permeable mean? Selectively lets things in and out.
List the 3 types of passive transport and define them:
1. Diffusion = movement of molecules with the concentration gradient.
2. Osmosis = the diffusion of water from an area of high concentration to low concentration gradient.
3. Facilitated Diffusion = molecules that are too big require special channel proteins to move across the cell membrane.
Describe in as many ways as possible how you know when a system has reached equilibrium:
The system will stop moving once equilibrium is reached. Molecules will be spread out evenly throughout the solution.
Use the word bank above to help you answer the following short answer questions.
isotonic, hypotonic, hypertonic, diffusion, osmosis, concentration gradient, cell membrane, selective permeability
If you were to drink salt water from the ocean (which has a very high concentration of salt ions), what would happen to your cells? Your cells would be in a hypertonic solution and would cause the cell to shrivel and shrink.
What will happen if a cell has an oxygen concentration that is higher outside of the cell compared with the inside of the cell (see picture below):
Diffusion would occur and oxygen would to the inside of the cell because of the concentration gradient.
List the 3 types of active transport and define them:
1. Protein pumps = proteins pump molecules against the concentration gradient.
2. Exocytosis = A large amount of molecules that use a vesicle to exit the cell.
3. Endocytosis = A large amount of molecules enter the cell by forming a vesicle.
What is the difference between active transport and passive transport? Active transport requires energy and passive transport does not.
Label each of the following figures below with one of the following terms: exocytosis, active transport, endocytosis, or facilitated diffusion. Draw a star next to the figures that require energy.
**Endocytosis** **Exocytosis** Facilitated Diffusion **Active transport**