Download Fall Semester Final Exam – Biology Review Answers

Fall Semester Final Exam – Biology Review Answers
1.
Define the following terms:
Abiotic Factor: a non-living factor such as climate, weather, soil, air pollution or water availability.
Biotic Factor: a living factor in an ecosystem, such as food availability, predator-prey relationships
and symbiotic relationships.
Symbiotic Relationship: a non-predator-prey relationship between two different species in which at
least one species gains a benefit.
Parasite: an organism that uses a host organism as a food source or reproduction site in a symbiotic
relationship. The host is not usually killed by the parasite, so it is not a predator-prey relationship.
Predator: an animal that hunts and kills other animals, called its prey, for food.
Prey: animal that is hunted and killed by predators.
Carnivore: animal that eats only animals that it hunted and killed for food; a predator.
Herbivore: animal that eats only plants for food.
Producer: plants that make food from sunlight; also called an autotroph.
Consumer: animals that eat other organisms (plants or animals) for food; also called heterotroph.
Decomposer: organisms that eat dead plants and animals, returning the nutrients to the soil.
2.
In the food web shown to the right, what
are the producers? Plants.
What are the first level consumers?
Sparrows, rabbits, mice and squirrels.
What are the second and third level
consumers? Owls, hawks and foxes.
If the mice in this food web all died from a
disease, which predator would be most
harmed? The owls, because they only have
two different prey species, rabbits and
mice. When the mice die, the only prey
left will be the rabbits.
3.
What is a mangrove forest? A tropical forest that grows in the shallow salt water of deltas and
estuaries. The roots branch out from the tree trunk above the water line, trapping soil and creating
shelter for many organisms. What functions do mangrove forests perform for coastal ecosystems?
Mangrove forests provide nesting sites for birds, and create a nursery for many aquatic species. It
helps stabilize and build land along tropical coasts.
4.
How do plants compete for resources in a tropical forest? The two limited resources in tropical
rainforests are light and soil nutrients. Trees and vines than can grow quickly and tall to reach the
light win the competition. Vines use trees for support to reach the light, and may eventually kill the
tree by shading out all the light and getting most of the soil nutrients.
5.
What is primary and secondary succession? Succession is the process in which plant communities
change over time. Primary succession happens when new land is formed or after a volcanic eruption
occurs, and new soil has to be created. Secondary succession happens after a forest fire or other
disturbance which does not destroy the existing soil, to rebuild the community of plants. What role
does succession play in the environment? Succession allows ecosystems to be built up and repaired to
reach a stable climax community. It can also allow for the transition from one community to
another, such as when a pond fills in with sediment over time, creating a meadow.
6.
What is biodiversity? Biodiversity is a measure of how many different species live in an area. Tropical
rainforests have the greatest biodiversity, while deserts and polar areas have the lowest.
What are the advantages of biodiversity in a natural ecosystem? Biodiverse ecosystems are more
stable, because each organism has more sources of food, and any niches that become open through
extinction or disease are quickly filled. Humans discover many new drugs to cure disease in tropical
rainforests, because of the great biodiversity. Why does a farmer not want a biodiverse field?
Farmers want to maximize their profit by growing as much of a single crop as possible. Other species
growing in the same field will lower profits, even if that greater biodiversity would be better for the
environment.
7.
Why is the use of fertilizers on farms a problem for oceans? Excess fertilizer washes off of fields and
into rivers, where it causes algae to bloom either in the river or in the ocean where the river flows.
When the fertilizer is used up, the algae dies and is decomposed by bacteria, which use up all the
oxygen in the water. This causes all fish to die from lack of oxygen, creating a “dead zone.”
8.
How can pollution from coal burning factories and power plants harm an ecosystem? The dust and
heavy metals such as mercury in the coal smoke settles onto the land, and washes into rivers and
lakes, poisoning the fish in the lakes and rivers.
9.
Describe the process of natural selection, and give an example of a species with a unique body shape
that evolved through the process of natural selection. Natural selection is the process by which
organisms that are suited to a particular environment are better able to survive and reproduce than
less-well adapted organisms. For example, anteaters have a long nose and tongue to better eat ants,
and giraffes have a long neck to better reach the leaves in tall trees.
10.
What is a heterotroph? An organism that must eat other organisms to get their energy.
11.
What is an autotroph? An organism that makes its own food through the process of photosynthesis.
12.
Into what six different kingdoms are living organisms classified? For each of the six kingdoms, state
whether it contains only single celled, only multi-celled, or both single and multi-celled organisms, and
whether it contains only autotrophs, only heterotrophs, or both autotrophs and heterotrophs.
(1) Archeabacteria: single celled, both autotrophs and heterotrophs.
(2) Eubacteria: single celled, both autotrophs and heterotrophs.
(3) Protists: mostly single celled, but few multicelled; most are heterotrophs, but some autotrophs.
(4) Fungi: mostly multicelled, but some single-celled; all are heterotrophs that digest food externally.
(5) Animals: all multi-celled, all heterotrophs that digest food internally.
(6) Plants: all multi-celled; all autotrophs.
13.
What are the four main ideas in cell theory? (1) all living organisms are made of cells; (2) all cells are
made from other cells; (3) all of the functions within living organisms are performed within cells;
(4) the cell is the main unit of structure and organization in all living organisms.
14.
For each of the following cell structures or organelles, state its function, and whether it is found only in
plant cells, only in animal cells, or both animal and plant cells.
Cell Wall: in plant cells only, provides support and structure for plant.
Cell Membrane: in both plants and animals, controls entry of materials in and out of cell.
Nucleus: storage of genetic material, which contains operating instructions and reproduction plans.
Central Vacuole: in plant cells only, provides storage of sugar, water and other materials; in animal
cells, there are many smaller vacuoles, but no large central vacuole.
Mitochondria: converts sugar into ATP, which provides energy for cell functions.
Chloroplast: in plant cells only; uses sunlight, carbon dioxide and water to make sugar and oxygen.
Endoplasmic Reticulum: maze-like structure around nucleus where proteins are assembled.
Golgi Bodies: storage and transport vessels, which carry assembled proteins to cell membrane.
15.
In the plant cell diagram to the right,
Chloroplasts
Golgi Bodies
identify all of the labeled organelles
and structures by listing the letter next
to the organelle description above.
Central
Vacuole
Mitochondria
Nucleus
Cell Wall
Endoplasmic Reticulum
16.
Where are the genetic instructions of all living organisms stored? In the nucleus.
17.
When an organism reproduces by asexual reproduction, how many parents does the organism have?
One. What are the advantages and disadvantages of asexual reproduction? The advantages of
asexual reproduction are that it is very fast and simple, allowing rapid population growth, and that
populations can grow even from a single organism. The main disadvantage is that all of the
organisms are exact clones, with no gene diversity to allow adaptation to a changing environment.
18.
When an organism reproduces by sexual reproduction, how many parents does the organism have?
Two. What are the advantages and disadvantages of sexual reproduction? The main disadvantages of
sexual reproduction are that it is slow and complex, and requires some population density in which
mates can be found. As a result, early population growth can be very slow. The main advantage of
sexual reproduction is the creation of a very diverse gene pool, which allows species to adapt quickly
to changing conditions, and makes it less likely that the species will go extinct due to disease.
19.
State the main function for each of the following human body organ systems:
Circulatory: delivers materials to all cells through blood vessels.
Digestive: breaks food down into small particles that can be carried in circulatory system.
Respiratory: exchanges oxygen and carbon dioxide between blood and atmosphere.
Excretory: filters blood and removes waste products and excess water for disposal.
Endocrine: regulates body systems through release of hormones into the blood stream.
Integumentary: (skin and hair) covers and protects the organism, keeping water in and germs out.
Nervous: controls all processes in the organism, and processes sensory input and motor output.
20.
What is a dichotomous key, and how is it used? It is a series of questions used to identify species
based on their characteristics.
21.
Identify the fish to the right using the dichotomous key below.
1. Fish shape is long and thin…………………………………......……go to step 2
Fish shape is not long and thin……………………………..……...go to step 3
2. Fish has pointed fins……………………………………………….……...trumpet fish
Fish has smooth fins……………………………………….…………..….spotted moray eel
3. Fish has both eyes on top of the head…………………….……..go to step 4
Fish has one eye on each side of the head…………….………go to step 5
Spotted Goat Fish
4. Fish has long whip-like tail……………………………………………..spotted eagle ray
Fish has short, blunt tail………………………………………….………peacock flounder
5. Fish has spots…………………………………………………………….…...go to step 6
Fish does not have spots…………………………………………….…..go to step 7
6. Fish has chin "whiskers"………………………………………………….spotted goat fish
Fish does not have chin "whiskers"….…………………..……….band-tail puffer
7. Fish has stripes……………………………………………………..………..go to step 8
Fish does not have stripes……………………………………..……….glassy sweeper
8. Fish has a v-shaped tail…………………………………………..……..squirrel fish
Fish has a blunt tail……………………………………………..………….glass-eye snapper
(The dichotomous key on the test will be the same as above, but the fish to be identified will be
different. Do not memorize the fish name in this review question; it will be a different fish on the test!)
93 possible
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