Transcript chapter

Active Lecture Questions
CHAPTER
3
Cells:
The Living
Units
Copyright © 2010 Pearson Education, Inc.
The basic functional unit of living
organisms is the __________.
a. element
b. organism
c. cell
d. organ
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The three main components of all cells
include the plasma membrane, the nucleus,
and the __________.
a. DNA
b. cytoplasm
c. organelle
d. cell wall
Copyright © 2010 Pearson Education, Inc.
The model describing the structure of the
cell membrane is known as the __________.
a. “sandwich” model
b. “fabric” model
c. “mosaic tile” model
d. “fluid mosaic” model
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Phospholipids orient themselves in
aqueous solutions such that __________.
a. the polar heads are pointed toward the
center of the membrane
b. the nonpolar tails are oriented toward the
interior of the cell, next to the cytoplasm
c. the polar heads and nonpolar tails
alternate facing inward
d. the polar heads face the interior and
exterior of the cell with the tails forming
the center of the membrane
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A cell might alter its membrane fluidity
(flexibility) by increasing the amount of
_________ in the cell membrane.
a. unsaturated fatty acids
b. lipid rafts
c. saturated fatty acids
d. proteins
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Because of the lipid content, the interior of
the membrane is __________.
a. hydrophobic
b. hydrophilic
c. water loving
d. solid
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The component of the cell membrane
primarily responsible for its functionality is
the ____________.
a. phospholipid
b. cholesterol
c. fatty acid
d. protein
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Proteins that are fully or partially embedded
in the cell membrane are called__________.
a. bilayer proteins
b. peripheral proteins
c. integral proteins
d. glycocalyx proteins
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In areas of the body subject to a higher
degree of mechanical stress, which of the
following types of membrane junctions
would you expect to be most prevalent?
a. Desmosomes
b. Microvilli
c. Tight junctions
d. Gap junctions
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In areas of the body where synchronization
of cellular activity is crucial for function,
which of the following types of membrane
junctions would you expect to be most
prevalent?
a. Desmosomes
b. Microvilli
c. Tight junctions
d. Gap junctions
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Based on your knowledge of the cell
membrane’s chemistry, where would
steroid hormones most likely interact with
their target cell?
a. Through interaction with an integral
membrane protein
b. Inside the target cell’s cytoplasm or
nucleus
c. Steroid hormones don’t interact with target
cells
d. On the exterior surface of the cell
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A red blood cell placed into a container of
distilled water will ________ water via
____________.
a. gain; diffusion
b. gain; osmosis
c. lose; diffusion
d. lose; osmosis
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Which of the following is not an example of
simple diffusion?
a. Gas exchange in our lungs
b. A dissolving sugar cube
c. Popcorn odor permeating the room
d. A white blood cell engulfing a bacterium
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The sodium-potassium pump __________.
a. pumps Na+ and K + out of the cell
b. pumps Na + and K + into the cell
c. pumps Na + into and K + out of the cell
d. pumps Na + out of and K + into the cell
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When movement of Na+ ions down their
concentration gradient drives the transport
of other substances across the cell
membrane, it is called___________.
a. primary active transport
b. secondary active transport
c. vesicular transport
d. pumping
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Cells that store large quantities of
chemicals to be released do so in
structures called ____________.
a. snares
b. docking sacs
c. fusion sacs
d. vesicles
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In areas of the body exposed to the external
environment and pathogens, such as in the
lungs, which type of vesicular transport
would you expect to be most prevalent?
a. Exocytosis
b. Pinocytosis
c. Phagocytosis
d. Receptor-mediated endocytosis
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You would expect that cells that expend a
great deal of energy, such as skeletal
muscle cells, would have increased
quantities of ___________.
a. ribosomes
b. smooth endoplasmic reticulum
c. peroxisomes
d. mitochondria
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Intensely biosynthetic secretory cells such
as neurons would be expected to have
greater amounts of _________ than other
cells.
a. centrioles
b. lysosomes
c. rough endoplasmic reticulum
d. peroxisomes
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The presence of which of the following
cytoskeletal elements endows cilia with the
ability to move and bend?
a. Intermediate filaments
b. Microtubules
c. Microfilaments
d. Actin filaments
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Which of the following cell types does not
possess a nucleus at maturity?
a. Skeletal muscle cells
b. Red blood cells
c. Bone destruction cells
d. Liver cells
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During which stage of the cell’s life cycle is
DNA replicated?
a. G1
b. S
c. G2
d. M
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The ________ stage of the neuron cell cycle
is the reason that permanent muscle
paralysis occurs.
a. interphase
b. G0
c. G2
d. G1
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The main function of DNA is to dictate
___________ production.
a. protein
b. carbohydrate
c. lipid
d. nucleic acid
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Every three nucleotides in a gene code for
_________ amino acid(s).
a. three
b. two
c. one
d. no
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The molecule that interacts with ribosomes
to dictate protein production is _______.
a. a nucleotide
b. DNA
c. transfer RNA
d. messenger RNA
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Cell differentiation occurs when early
embryo cells _________.
a. cut out part of the DNA and destroy it
b. switch off certain unneeded genes
c. separate and form the different parts of
the body
d. die in the process of apoptosis
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Apoptosis, or “programmed cell death,” is
_________.
a. abnormal
b. responsible for removing unnecessary
tissue such as the webbing between our
embryonic fingers and toes
c. dangerous
d. responsible for creating twins
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_________ is the process whereby mRNA is
made.
a. DNA replication
b. Translation
c. Transcription
d. mRNA editing
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____________ is the process whereby
protein is made.
a. DNA replication
b. Translation
c. Transcription
d. mRNA editing
Copyright © 2010 Pearson Education, Inc.