Download Fourth Nine Weeks Study Guide Answers

Fourth Nine Weeks Study Guide Answers
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
1. DNA molecule is shaped like a
spiral staircase.
2. During DNA replication, adenine (A) always pairs with
thymine (T).
3. Each rung of the DNA ladder is made of
a pair of nitrogen bases.
4. All organic compounds contain the element
carbon.
5. Why is water important for a cell?
Most chemical reactions in cells require water.
6. Enzymes are important because they
speed up chemical reactions.
7. Sugar molecules can combine with one another to form large molecules
called
Starches
8. What does messenger RNA do during protein synthesis?
copies the coded message from the DNA and carries it into the cytoplasm
9.
Which nitrogen base in RNA is NOT part of DNA?
uracil
10.
What is the function of a cell membrane?
to control what enters and leaves the cell
11. Which organelle is the control center of a cell?
nucleus
12. What is the function of a cell wall?
to protect and support the cell
13. Which organelles store food and other materials needed by the cell?
vacuoles
14. Which organelles release chemicals that break down large food particles
into smaller ones?
lysosomes
15. The way the endocrine system maintains homeostasis is often compared
to a
heating system that turns the furnace on and off to control a room
temperature
16. The endocrine system acts on the body through chemical products called
hormones
17 Which endocrine gland(s) link(s) the endocrine system and the nervous
system?
hypothalamus
18. Which endocrine gland(s) communicate(s) with the hypothalamus to
control many body activities, including growth from infancy to adulthood?
pituitary gland
19. The endocrine system often uses a negative feedback process to
maintain homeostasis.
20. The endocrine system produces chemicals that
control both daily activities and long-term changes through hormones.
21. When the nervous system makes you feel hungry or thirsty, what
body process is it helping to carry out?
maintaining homeostasis
22. A change or signal in the environment that can make an organism react is
called a(n)
stimulus.
23. What part of the brain controls memory?
cerebrum
24. A spinal nerve is made up of
Both sensory neurons and motor neurons
25. An automatic response of the body that occurs very rapidly and without
conscious control is called a(n)
reflex.
26. In some reflex actions, skeletal muscles contract without the involvement
of
the brain.
27. What is the name of the opening through which light enters the eye?
pupil
28. Nearsightedness and farsightedness are caused by
a defect in the shape of the eyeball.
29. If the semicircular canals are damaged, which sense will be affected?
balance
30. A synapse is the space between
an axon and the structure that receives the nerve impulse.(dendrite of the
next neuron)
31. The brain and spinal cord make up the
central nervous system
32. The three regions that make up the brain include the cerebrum, cerebellum,
and
Brain stem
33. Because of the way in which the lens of the eye bends light rays, the image
produced by the lens is
upside down.
34. What are the products photosynthesis
Oxygen and sugars
Short Answers
35. Describe the process of DNA replication. Why is replication important?
These are the steps of DNA replication
1. DNA unzips
2. Nitrogen bases floating in the nucleus pair up with each half on the DNA
molecule
3. Adenine pair up with thymine and cytosine pair up with guanine
4. Two DNA molecules are formed
36. Compare and contrast DNA and RNA?
DNA
BOTH
Double Stranded ladder
like structure
Made up of
Nitrogen bases adenine,
deoxyriboese sugar
guanine, cytosine
Nitrogen base Thymine
RNA
Single stranded
Made up of ribose
sugar
Nitrogen base uracil
37. Compare and contrast chloroplast and mitochondria.
Chloroplast
Both
Mitochondria
Traps energy from sun Involves with trapping Releases energy from
to make glucose(Sugar, or releasing energy
glucose
food)CELLULAR
PHOTOSYNTHESIS
RESPIRATION
Oval shaped structure
Organelles in
Oval shaped structure
in cells with straight
eukaryotic cellcell
with wavy lines
lines(plastids)
(cristae)
38. Explain how nerve impulse travels through the neuron?
The nerve impulse begins in dendrites Move to neurons cell
bodyMove through axon till it reaches axon tip move through
synapsemove to dendrite of next neuron
40. List the levels of organization from the most complex to the simplest?
OrganismOrgan SystemsOrgans 
TissuesCellsOrganellesChemicals