BIO 1030 Dynamic Study Mod Ch 4
Ions flow through _______ between cells of heart muscle. How does this help the heart do its job?
gap junctions: coordinate contraction
A cell that produces proteins for export contains large quantities of _______, while a muscle cell contains abundant _______.
rough endoplasmic reticulum: microfilaments
Which of the following is (are) the hydrophilic regions of the cell membrane? -the regions nearest to the external and internal environments -the regions farthest from the external and internal environments -the region buried deeply within the membrane bilayer -the region closest to the nucleus -the regions with embedded proteins
the regions nearest to the external and internal environments
The light microscope can magnify specimens by at most ______ times and can resolve details down to about the size of _______.
1,000: 0.2 um
What effect do inherited lysosomal storage diseases have on cells? -accelerated rate of digestion due to the excess activity of lysosomal enzymes -buildup of digested material that cannot be removed from the cell -accelerated rate of recycling due to the absence of key lysosomal enzymes -buildup of undigested material due to the excess activity of lysosomal enzymes -buildup of undigested material because key lysosomal enzymes are absent
buildup of undigested material because key lysosomal enzymes are absent
What comes to mind when you hear the term "9 + 2"?
cilia and flagella
Which of the following lists includes only components that provide structural support, allow movement, or enable communication between cells? -cytoskeleton, plant cell wall, plasma membrane -cytoskeleton, Golgi apparatus, nucleus -Golgi apparatus, plasma membrane, flagella -mitochondria, Golgi apparatus, cytoskeleton -plant cell wall, nucleus, peroxisomes
cytoskeleton, plant cell wall, plasma membrane
Where do the chemical reactions of cellular respiration take place in plants?
in the matrix of the mitochondria
A differential interference contrast microscope uses __________ to examine a specimen. Which type of microscope would one use to examine the internal structure of a nucleolus?
light: transmission electron microscope
Which of the following are present in animal cells but not in plant cells? -lysosomes, centrosomes, flagella -peroxisomes and flagella -lysosomes and peroxisomes -peroxisomes and centrosomes -lysosomes and centrosomes
lysosomes and centrosomes
Lysosomes contain digestive enzymes. Peroxisomes contain H2O2. Both the digestive enzymes and H2O2 can kill cells. How is it possible that cells can contain toxic substances without being damaged? Membranes isolate substances into separate compartments. -cells generally do not contain substances to which they are vulnerable. -membranes allow substances to move between compartments. -most cells contain buffers against substances like digestive enzymes and H2O2. -many cells are, in fact, killed, but enough survive to do their jobs.
membranes isolate substances into separate compartments
Consider a free ribosome. What enters this organelle, and what comes out of it, in the process of protein synthesis? -ribosomal RNA (rRNA) enters: a polypeptide comes out -messenger RNA (mRNA) enters: a polypeptide comes out -DNA enters: messenger RNA (mRNA) comes out -messenger RNA (mRNA) enters: ribosomal RNA comes out -DNA enters: a polypeptide comes out
messenger RNA (mRNA) enters: a polypeptide comes out
Which of the following lists the smallest of the cell's cytoskeletal elements, and what is the function of these elements? -intermediate filaments: muscle contraction -microfilaments: form "tracks" for movement of lysosomes -microfilaments: main component of cilia -microtubules: main component of flagella -microfilaments: muscle contraction
microfilaments: muscle contraction
Which of the following organelles is present in a prokaryotic cell, but not a eukaryotic cell? -nucleus -nuclear envelope -nucleoid -plasma membrane -nucleolus
nucleoid
Ribosomal RNA is produced in the ________ according to instructions from the cell's _________. Subunits are then formed from ribosomal RNA and ______ imported from the cytoplasm. -nucleolus: DNA: proteins -smooth ER: DNA: proteins -golgi apparatus: DNA: lysosomes -cytoplasm: DNA: vesicles
nucleolus: DNA: proteins
All of the following originate from the endomembrane system EXCEPT _______. -peroxisomes -lysosomes -food vacuole -rough ER -smooth ER
peroxisomes
The cell wall of plants consists of which of the following substances? -polysaccharides -proteins -cellulose -polysaccharides and proteins -polysaccharides and lipids
polysaccharides and proteins
Which of the following functions is performed by the Golgi apparatus? -processing proteins for use within the cell only -processing proteins for secretion only -manufacturing lipids and enzymes -processing proteins for secretion and for use within the cell -folding proteins prior to export
processing proteins for secretion and for use within the cell
Which of the following organelles is responsible for folding proteins and adding the short sugar chains that make them glycoproteins? -rough ER -golgi apparatus -transport vesicle -ribosome -smooth ER
rough ER
According to the endosymbiont theory, what benefit was gained when the ancestor of the eukaryotic cell incorporated a photosynthetic prokaryote? -the cell acquired membrane-bound organelles. -the newcomer provided nourishment to its host. -organic molecules could be used to provide energy. -the rate of cellular respiration was greatly accelerated. -the cell became more effective in warding off predators
the newcomer provided nourishment to its host
Which of the following can perform these functions in plants: digestion, water circulation, pigmentation, and food storage?
vacuole