Biology Semester I Exam REVIEW– 2015-2016
1.
Provide a brief description of DNA Replication:
The DNA strand is pulled apart by helicase and used as a template (model)
for the new strands to be synthesized (built)
2.
What is the importance of having a checkpoint after synthesis in the cell
cycle? To make sure that DNA replication is correct and there are no
mistakes.
3.
During DNA replication, mistakes are made and the wrong nucleotide is
added to the new strand of DNA. This is called a mutation. What could a
mutation possibly lead to? CANCER
4.
Surtsey is an island south of Iceland. The island was formed by a volcanic
eruption and first appeared in 1963. The table below contains descriptions
of changes in the population and diversity of species on Surtsey.
List the descriptions in the correct order of ecological succession on Surtsey:
7.
Bacteria living in the soil and on the roots of some plants are important in
the cycling of which essential element in an ecosystem? NITROGEN
8.
What simple molecule reacts with itself to form this disaccharide?
GLUCOSE :Ring shaped and NOLY made of C, H and O
9.
What is the function of nucleic acids? Stores genetic information to make
PROTEINS
10. The subunits of a protein are— AMINO ACIDS
II, IV, I, III
5.
Commensalistic interactions between species are rare. Give an example of
this type of symbiotic relationship: One species benefits and the other is
not affected: Whales and barnacles
6.
Bubble net feeding is unique to humpback whales. A pod of whales swims
below a school of fish, such as herring, and blows bubbles under the fish,
continuously encompassing the fish in an increasingly smaller circle.
Eventually, the whales lunge toward the surface of the water, gulping huge
amounts of both water and fish in their mouths. They force the water out
of their mouths and ingest only fish.
The type of feeding relationship between whales and herrings is —
PREDATION
11. Explain the process illustrated in the diagram.
Molecules are moving from higher to low concentration across the cell membrane
with the HELP of proteins (Facilitated Diffusion)
Biology Semester I Exam REVIEW– 2015-2016
16. A plant is left unwatered for two weeks. What do you expect to happen in
the plant? Sunlight + Water + Carbon Dioxide -- Oxygen + Glucose
The water (reactant) will decrease so the rate of photosynthesis will also
decrease
17. What analogy best represents cancer? Weeds growing out of control and
taking over a garden
18. Define DNA: It is a long term storage genetic information, are the
instructions for making proteins and is called “blueprints” or a “recipe”
12. What additional characteristic (X) belongs in the central section of the
Venn diagram? RIBOSOMES
13. What characteristic defines this organism as eukaryotic? NUCLEUS
14. Explain the difference between the way animals and plants exchange gases
with their environments: Animals use only Cellular Respiration but plants
and animals use both Cellular Respiration and Photosynthesis
15. What could lead to a lower rate of cell respiration in an animal?
Glucose + Oxygen --- Carbon dioxide + Water =ATP
A decrease in either glucose or oxygen would cause cell respiration to
decrease because the reactants are needed to make the products
19. A marine ecosystem is represented below.
What is lost to the environment at each trophic levels of this
ecosystem? HEAT
Biology Semester I Exam REVIEW– 2015-2016
20. A model of a DNA molecule is shown below.
The arrow indicates — HYDROGEN BOND
25. The diagram shows a portion of a DNA molecule.
Describe the products of DNA Replication: There are two new strands each
strand half of the original DNA and half new DNA (semi-conservative
21. What must occur during S phase of the cell cycle so that two daughter
cells can be produced during M phase? DNA REPLICATION
22. Enzymes are proteins that help increase the rate of chemical reactions
inside cells. These proteins are composed of many simpler molecules called
amino acids. What suggests that the shape of an enzyme determines the
enzyme’s function? Enzymes can not work on any substrate, they have
specific substrates that they can work on EX: Amylase works only on sugars
during digestion
23. What is the main difference between prokaryotes and eukaryotes?
PROkayotes = NO (they do not have a nucleus or membrane bound
organelles)
Eukaryotes – DO (they DO have a nucleus and membrane bound organelles)
24. When in the cell cycle does DNA replication in the cell cycle of eukaryotes?
During the S phase of the cell cycle BEFORE mitosis divides the daughter
cells in two.
replication)
26. In 1952 Rosalind Franklin took the x-ray photograph shown below, which
gave the world its first look at DNA.
By studying this photograph, scientists gained knowledge about the—
The double helix structure of the DNA molecule
27. What biomolecule typically contains both nitrogen and phosphate?
DNA: Contains C, H, O, N and P
Biology Semester I Exam REVIEW– 2015-2016
28. The diagram below represents the nitrogen cycle in a student’s aquarium.
Ammonia, nitrites, and, to a lesser degree, nitrates can be harmful to fish.
The student wants to keep the nitrogen in this aquarium cycling normally
without having to continually change the water.
What should the student add more of to help remove nitrates and improve the
natural cycling of nitrogen in this aquarium? Add more plants to the aquarium.
Nitrogen is taken up by the plants because they need to use it as a nutrient for
growth.
29. Which of these best represents a fatty acid molecule?
F: It has a LONG chain with LOTS of bonds and made of C, H and O
30. Carbohydrates are more easily metabolized than lipids. However, on a gramfor-gram basis lipids provide cells with more ENERGY