BIO 181 Week 03 Cell Components
Which of the following is false in respect to cells' chromosomes? Chromosomes contain DNA and proteins. Chromosomes exist even when cells are not actively synthesizing proteins. Chromosomes are present throughout a cell's reproductive cycle. Chromosomes are only visible as a cell is about to divide.
Chromosomes are only visible as a cell is about to divide.
Which statement about the cytoskeleton is true? Microtubules are chains of proteins that resist stretching. Intermediate filaments are hollow tubes of protein that provide structural support. Components of the cytoskeleton often mediate the movement of organelles within the cytoplasm. Microfilaments are more permanent structures in cells compared to intermediate filaments and microtubules. Plant cells lack a cytoskeleton because they have a rigid cell wall.
Components of the cytoskeleton often mediate the movement of organelles within the cytoplasm.
Cilia and flagella move due to the interaction of the cytoskeleton with which of the following? Actin Motor proteins Tubulin Pseudopodia Mitochondria
Motor proteins
Which of the following is present in a prokaryotic cell? Ribosomes Chloroplast Mitochondrion ER Nuclear envelope
Ribosomes
Which of the following groups is primarily involved in synthesizing molecules needed by the cell? Lysosome, vacuole, and ribosomes Smooth endoplasmic reticulum, ribosomes, and vacuole Vacuole, rough endoplasmic reticulum, and smooth endoplasmic reticulum Ribosomes, rough endoplasmic reticulum, and smooth endoplasmic reticulum Rough endoplasmic reticulum, lysosome, and vacuole
Ribosomes, rough endoplasmic reticulum, and smooth endoplasmic reticulum
Your intestine is lined with individual cells. No fluids leak between these cells from the gut into your body. Why? The intestinal cells are bound together by plasmodesmata. The intestinal cells are bound together by the extracellular matrix. The intestinal cells are fused together into one giant cell. The intestinal cells are bound together by tight junctions. The intestinal cells are bound together by gap junctions.
The intestinal cells are bound together by tight junctions.
Animal cells have unique organelles called __________ that are composed of structures called __________. centrioles; centrosomes nucleosomes; centrioles centrosomes; nucleosomes centrosomes; centrioles centromeres; centrioles
centrosomes; centrioles
Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell they __________. lack a plasma membrane have no ribosomes have no membrane-bounded organelles in their cytoplasm have a smaller nucleus lack chromosomes
have no membrane-bounded organelles in their cytoplasm
Observing a fluorescent micrograph cell with intermediate filaments would help you identify the cell as a __________. human skin cell eukaryotic cell fungal cell plant cell prokaryotic cell
human skin cell
A protein that ultimately functions in the plasma membrane of a cell is most likely to have been synthesized __________. in the plasma membrane on free cytoplasmic ribosomes in the ribosomes of the mitochondria in the rough endoplasmic reticulum in the smooth endoplasmic reticulum
in the rough endoplasmic reticulum
The walls of plant cells are largely composed of polysaccharides and proteins that are synthesized __________. in the smooth endoplasmic reticulum externally to the plasma membrane in the Golgi apparatus in the rough endoplasmic reticulum in the rough endoplasmic reticulum and in the Golgi apparatus
in the rough endoplasmic reticulum and in the Golgi apparatus
The network of fibers that organizes structures and activities in a cell __________. are intermediate filaments are microfilaments is the cytoskeleton are centrioles are microtubules
is the cytoskeleton
The endosymbiont theory explains the origins of __________. There is no correct answer because the endosymbiotic theory is no longer supported. the Golgi apparatus and mitochondria chloroplasts and the plant cell vacuole mitochondria and chloroplasts mitochondria and ribosomes
mitochondria and chloroplasts
The region of a bacterial cell that contains the genetic material is called the __________. nucleus nucleolus nucleosome nucleoid capsule
nucleoid
Cells are small because __________. area is proportional to a dimension cubed (X3), whereas volume is proportional to a dimension squared (X2) small cells are easier to back together of the geometric relationships between surface and volume None of the listed responses is correct. smaller objects have a smaller ratio of surface to volume
of the geometric relationships between surface and volume
Dye injected into a plant cell might be able to enter an adjacent cell through __________. a gap junction a tight junction a microtubule plasmodesmata a cell wall
plasmodesmata
Cell motility, which includes changes both in cell location and in the movement of cell parts, requires interactions of the cytoskeleton __________. with "feet" to "walk" with the endoplasmic reticulum with motor proteins without ATP with glycosomes
with motor proteins
Basal bodies are most closely associated with which of the following cell components? The central vacuole Mitochondria Golgi apparatus Nucleus Cilia
Cilia
In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? Eukaryotic cells are compartmentalized, which allows for specialization. Eukaryotic cells are much more successful than prokaryotic cells. Eukaryotic cells can synthesize proteins but prokaryotic cells cannot. Eukaryotic cells are larger than prokaryotic cells. Eukaryotic cells lack many of the organelles found in prokaryotes.
Eukaryotic cells are compartmentalized, which allows for specialization.
__________ are membrane-bound metabolic compartments that specialize in the production of hydrogen peroxide (H2O2) and its conversion to water. Lysosomes Ribosomes Nucleosomes Centrosomes Peroxisomes
Peroxisomes
What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane? The nucleolus contains messenger RNA (mRNA), which crosses the nuclear envelope through the nuclear pores. Endoplasmic reticulum membrane is produced in the nucleolus and leaves the nucleus through the nuclear pores. Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores. The nuclear pores are connections between the nuclear membrane and the endoplasmic reticulum that permit ribosomes to assemble on the surface of the ER.
Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores.
The extracellular matrix of the animal cell has all of the following molecular components except __________. fibronectin a middle lamella integrins proteoglycans collagen
a middle lamella
The organelle that is a plant cell's compartment for the storage of inorganic ions such as potassium and chloride is the __________. central vacuole lysosome food vacuole plastid contractile vacuole
central vacuole
Microfilaments function in cell motility including __________. muscle contraction, amoeboid movement, and centriole function flagella motion, cilia motion, and centriole function muscle contraction, amoeboid movement, and cilia motion muscle contraction, amoeboid movement, and cytoplasmic streaming in plants muscle contraction, amoeboid movement, and flagella motion
muscle contraction, amoeboid movement, and cytoplasmic streaming in plants
The endoplasmic reticulum is part of the endomembrane system, which also includes the __________. nuclear envelope, the Golgi apparatus, and mitochondria mitochondria, the Golgi apparatus, lysosomes, and vesicles nuclear envelope, the Golgi apparatus, mitochondria, and chloroplasts nuclear envelope, the Golgi apparatus, and ribosomes nuclear envelope, the Golgi apparatus, lysosomes, and vesicles
nuclear envelope, the Golgi apparatus, lysosomes, and vesicles
Cell junctions in plant cells are called __________, and communicating junctions in animal cells are called __________. plasmodesmata; gap junctions desmosomes; plasmodesmata plasmodesmata; tight junctions tight junctions; gap junctions gap junctions; plasmodesmata
plasmodesmata; gap junctions
You would expect a cell with an extensive Golgi apparatus to __________. absorb nutrients in the GI tract make a lot of ATP store large quantities of ions secrete a lot of protein move rapidly
secrete a lot of protein
Evidence that supports the prokaryotic origins of mitochondria and chloroplasts are all of the following except __________. that the ancestral prokaryote had two outer membranes, which became the double membranes of the mitochondria and chloroplasts that mitochondria and chloroplasts have multiple copies of circular DNA molecules associated with their membranes that mitochondria and chloroplasts can grow and reproduce within a cell that mitochondria and chloroplasts are somewhat independent within a cell that mitochondria and chloroplasts have multiple copies of linear DNA molecules associated with their inner membranes
that mitochondria and chloroplasts have multiple copies of linear DNA molecules associated with their inner membranes
A substance moving from outside the cell into the cytoplasm must pass through __________. a microtubule the plasma membrane a ribosome the nucleus the endomembrane system
the plasma membrane
The function of the rough endoplasmic reticulum (RER) is __________. to synthesize lipids to synthesize sex hormones to store calcium ions to synthesize proteins that are secreted as glycoproteins to detox drugs and alcohol
to synthesize proteins that are secreted as glycoproteins