Functional Bio chapter 7
For prokaryotic cells, which statement is correct concerning how the structure of a particular cell component correlates with its function? See Section 7.1 (Page) . View Available Hint(s) The cell wall represents infoldings of the plasma membrane that protect the cell and give it shape and rigidity. Photosynthetic membranes are composed of crosslinked polymers like peptidoglycan that provide extensive surface area for photosynthesis. The cell wall is a tough, fibrous layer that protects the cell and gives it shape and rigidity. Photosynthetic membranes contain magnetite that allows the cell to convert magnetic field energy into chemical energy.
The cell wall is a tough, fibrous layer that protects the cell and gives it shape and rigidity.
Which of these organelles carries out cellular respiration? smooth endoplasmic reticulum ribosomes chromatin mitochondrion nucleolus
mitochondrion: Mitochondria convert the chemical energy of organic molecules to chemical energy in the form of ATP.
Which of these structures stores, modifies, and packages products: See second picture
A The Golgi apparatus modifies, stores, and packages products of the ER
_____ is/are identical in structure to centrioles. Basal bodies Chromatin Nuclear envelopes Microfilaments Mitochondria
Basal bodies: Basal bodies and centrioles have identical structures
Choose the letter that indicates the organelle that contains most of a cell's DNA. See second picture
C The nucleus contains most of a cell's DNA.
The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____. See first picture
C. plasma membrane
What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell? capsule pili cell wall flagella nucleoid region
Cell wall
Which of these provides the cell with structural support? See second picture
D Microfilaments are a component of the cytoskeleton
The DNA-containing region of this bacterial cell is indicated by the letter _____. See first picture
D nucleode region
Which molecules do not normally cross the nuclear membrane? View Available Hint(s) DNA Proteins mRNA Nucleotide triphosphates
DNA: All processes involving DNA take place in the nucleus
Which of these is the double membrane that encloses the nucleus? See second picture
E Correct This is the nuclear envelope
What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? ER → lysosomes → vesicles that fuse with plasma membrane ER → Golgi → nucleus nucleus → ER → Golgi Golgi → ER → lysosome ER → Golgi → vesicles that fuse with plasma membrane
ER → Golgi → vesicles that fuse with plasma membrane
True or false? Large proteins containing a nuclear localization signal (NLS) bind to the nuclear pore and enter the nucleus without any expenditure of energy.
False Cytoplasmic proteins called importins bind to large proteins containing an NLS and mediate their transport across the nuclear membrane through an active transport (energy-requiring) process.
_____ are surface appendages that allow a bacterium to stick to a surface Flagella Cell walls Fimbriae Mitochondria Ribosomes
Fimbriae
As proteins are manufactured on Rough Endoplasmic Reticulum (R E R), they move into the lumen. What is a lumen?
Lumen—inside of any sac-like structure
Which of these are hollow rods that shape and support the cell? chloroplasts peroxisomes microtubules microfilaments plasma membrane
Microtubules: Microtubules are rods that also play a role in organelle movement
Which answer is the best match between a specialized cell type and its subcellular structure? See Section 7.3 (Page) . View Available Hint(s) Muscle cells: packed with secretory vesicles Muscle cells: packed with mitochondria Pancreas cells: packed with chloroplasts Fat cells: packed with mitochondria
Muscle cells: packed with mitochondria
Nucleoplasmin is a nuclear protein. This protein was divided into two segments and linked to the same large cytoplasmic protein, generating two fusion proteins. After injecting these fusion proteins into a cell, one of the proteins was found in the nucleus and the other in the cytoplasm. Which of the following conclusions can be drawn from these results? Nucleoplasmin does not have a nuclear localization signal. One of the fusion proteins entered the nucleus by passive transport. Only one of the two fusion proteins possesses a nuclear localization signal. The cytoplasmic protein contains a nuclear localization signal.
Only one of the two fusion proteins possesses a nuclear localization signal. The nuclear localization signal is only present in the fusion protein that enters the nucleus.
A small protein (molecular weight = 25,000 daltons) is injected into a cell and observed in the nucleus a short time later. What type of transport has taken place? View Available Hint(s) Passive transport Osmosis Active transport
Passive transport A 25,000-dalton protein is small enough to diffuse through nuclear pores without any expenditure of energy
Which of these organelles produces H2O2 as a by-product? mitochondrion centrioles peroxisome flagellum nucleus
Peroxisomes: Peroxisomes produce hydrogen peroxide as a by-product of their metabolic processes
____ are the sites of protein synthesis. Peroxisomes Golgi apparatuses Microfilaments Ribosomes Mitochondria
Ribosomes
Which of the following statements about the nuclear envelope is false? View Available Hint(s) The nuclear envelope is continuous with the Golgi apparatus. Molecules pass into and out of the nucleus through nuclear pores. Nuclear pores are made up of a group of proteins that are collectively called the nuclear pore complex. The nuclear envelope is composed of two lipid bilayers.
The nuclear envelope is continuous with the Golgi apparatus the nuclear envelope is continuous with the endoplasmic reticulum.
Which statement most accurately describes what happens to proteins that lack an ER signal sequence? They are inserted into the plasma membrane. They are inserted into the ER membrane but do not enter the ER lumen. They are released into the cytosol. They bypass the ER but enter the Golgi apparatus.
They are released into the cytosol. Ribosomes synthesizing proteins without ER signal sequences remain in the cytosol and release the proteins there
How are these signals read? They bind to motor proteins. They enter transport vesicles. They bind to receptor proteins. They are glycosylated by enzymes
They bind to receptor proteins
Eukaryotes do have a nucleus with a nuclear membrane. True or False
True Archaea and bacteria do not have a membrane-surrounded nucleus
The _____ is composed of DNA and protein centriole mitochondrion ribosome flagellum chromatin
chromatin
The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined by the _____. transportation of membrane lipids among the membranes of the endomembrane system by small membrane vesicles synthesis of different lipids and proteins in each of the organelles of the endomembrane system function of the Golgi apparatus in sorting and directing membrane components interconnection of most intracellular membranes to the nuclear envelope modification of the membrane components once they reach their final destination
function of the Golgi apparatus in sorting and directing membrane components
Endocytosis moves materials _____ a cell via _____. out of ... membranous vesicles into ... membranous vesicles into ... facilitated diffusion into ... a transport protein out of ... diffusion
into ... membranous vesicles
Where is a bacterial cell's DNA found? ribosomes nucleus peroxisome nucleoid region capsule
nucleoid region
Ribosomal subunits are manufactured by the _____. peroxisome rough endoplasmic reticulum nucleolus lysosome smooth endoplasmic reticulum
nucleolus
An organism with a cell wall would most likely be unable to take in materials through ________. osmosis facilitated diffusion phagocytosis diffusion active transport
phagocytosis
A white blood cell engulfing a bacterium is an example of _____. exocytosis phagocytosis facilitated diffusion receptor-mediated endocytosis pinocytosis
phagocytosis Phagocytosis occurs when a cell engulfs a large particle
The _____ is a selective barrier, regulating the passage of material into and out of the cell. plasma membrane nuclear envelope lysosome chloroplast nucleus
plasma membrane
What is a function of a bacterium's capsule? DNA storage protein synthesis protection propulsion
protection
In a bacterium, where are proteins synthesized? ribosomes nucleus peroxisome nucleoid region capsule
ribosomes
Which of these organelles manufactures proteins bound for secretion out of the cell? lysosomes rough endoplasmic reticulum Golgi apparatus nucleolus
rough endoplasmic reticulum: The ribosomes associated with the rough ER synthesize secretory proteins bound for the exterior of the cell. Further processing and packaging occurs in the Golgi apparatus.
Where is calcium stored? centrioles rough endoplasmic reticulum microtubules smooth endoplasmic reticulum mitochondria
smooth endoplasmic reticulum
You can recognize the process of pinocytosis when _____. the cell is engulfing extracellular fluid a receptor protein is involved the cell is engulfing a large particle
the cell is engulfing extracellular fluid