BIO Chapter 4
Enzymes called proteases in the ER lumen catalyze folding of proteins into proper conformations.
False
In scanning electron microscopy, an electron beam passes through a very thin slice of a specimen and then falls onto a photographic plate or a fluorescent screen.
False
Which two organelles are responsible for converting energy into forms that can be used by cells?
Mitochondria and chloroplasts
Briefly explain the relationship between the surface area and volume of a cell and overall cell size. List two ways in which organisms have successfully "solved" this problem.
Surface area of cell has to be large enough to support metabolism of cell volume
Microfilaments are linked with one another and with other proteins by linker proteins.
True
The smooth ER is the primary site for the synthesis of phospholipids and cholesterol needed to make____
cell membranes
What type of microscopy uses a laser to excite fluorophores in a thin slice through a cell ?
confocal microscopy
Name the part of the cell outside the nucleus.
cytoplasm
During an infection, white blood cells travel to the infected site and phagocytize the pathogens. After phagocytosis, primary lysosomes fuse with the phagocytic vesicle to form a larger vesicle called a secondary lysosome. The purpose is to...
degrade the pathogens into components, which the cell recycles/uses an energy source
nucleolus
granular body within an organelle which consists of RNA and protein
Which strategy is the most effective for larger cells to have an effective surface area to volume ratio?
having thin, finger-like projections
vacuoles
large membranous sacs of plants and fungi
Which of the following is a key component of the cytoskeleton?
microtubules
Intermediate filaments are most closely associated with
microvilli
What organelles plays an important role in apoptosis, or programmed cell death?
mitochondria
What enzyme in the ER lumen catalyze the efficient folding of proteins into proper conformations?
molecular chaperones
specialized structures within a living cell are known as...
organelles
A cell is surrounded by which distinctive surface membrane ?
plasma membrane
What is a characteristic found in both prokaryotic and eukaryotic cells ?
plasma membrane
What is the purpose of the cristae of the inner membrane of mitochondria?
to break down nutrients
What is the primary function of mitochondria?
transformation of energy
The micrometer (μm) is the most convenient unit for measuring cells
true
plastids
encloses an internal thylakoid membrane
The smooth ER is the primary site for the synthesis of proteins and cholesterol needed to make membranes.
False
Proteins that are synthesized by ribosomes may be further modified within what organelle ?
Golgi complex
Evidence that all living cells have a common origin is best illustrated by...
basic similarities in cell structure and chemistry
lysosome
membranous sacs in animals
If a bacterial toxin destroys ribosomes, what cellular activity will be affected first?
protein synthesis
What does nucleolus, within the nucleus, synthesize ?
ribosomal RNA
Rough ER
ribosomes stud its outer surface
Peroxisomes are found in large numbers in cells that synthesize, store, and degrade lipids, and one of their functions is to break down protein molecules.
False
A basal body anchors what part of a cell?
flagellum
The many short appendages that a cell has are called cilia.
True
Upon observing a cell of a grass blade, you notice a prominent sac that occupies a large portion of the cell. Which organelle is this?
Vacuole
Necessary for a cell to maintain its function and growth...
food
Briefly compare prokaryotic and eukaryotic cells. Identify three ways that differences between eukaryotes and prokaryotes impact cell function.
Both have cytoplasm, ribosomes, DNA, RNA, and plasma membrane. Difference is only eukaryotes have membrane bound organelles. Eukaryotes generate more ATP molecules
Plants lack organ systems for disposing of toxic metabolic waste products. Their cells' vacuoles are similar to which animal cell organelle?
Lysosomes
What technique is used to separate different part of cells so that they can be studied by both physical and chemical methods?
cell fractionation
DNA is associated with certain proteins, forming a complex called...
chromatin
The ratio of the size of the image seen w/ the microscope to the actual size of the object is called:
magnification
microfilaments
rodlike structures consisting of actin
The cis face of the Golgi complex is most directly involved in what process ?
Accepting vesicles from the ER
You isolate a cellular structure and determine that it is composed of α-tubulin and β-tubulin. Based on this evidence, you correctly identify this structure as a(n)
Actin filament
Identify two structural components of the cytoskeleton, and briefly describe their function(s).
Microtubules- move vesicles and organelles via special attachment proteins. Microfilaments- serve a role in cytokinesis, movement, and changes in cell shape