BI-216 Chapter 4 Cells and Organelles
Name the three components of the cytoskeleton
Microtubules, microfilaments, and intermediate filament
Membrane proteins may function in
Receiving extracellular signals
Which of the following organelles is not part of the endomembrane system?
Ribosome
Which sequence reflects the locations that a secretory protein will visit on its way from its production to its secretion outside the cell?
Rough ER, ER vesicle, Golgi complex, secretory vesicle
The cytosol is best described as the
Semifluid substance in which organelles are suspended
One difference between rough and smooth ER is that
Smooth ER is involved in drug detoxification
Prokaryotes have ____ ribosomes with ____ and ____ subunits, whereas eukaryotes have ____ ribosomes with ____ and ____ subunits.
70S, 50S, 30S, 80S, 60S, 40S
Which of these is NOT a component of the cell cytoskeleton?
Cellulose fibril
Which of the following is a true statement regarding lysosomes?
The lysosome may mature from a late endosome
A protein is destined to be secreted from a cell. In which organelle would you expect to find the protein just after it is produced in the rough endoplasmic reticulum?
Golgi apparatus
Name the two functions of the cytoskeleton
It organizes the cell's structure and activities, anchoring many organelles
The smooth endoplasmic reticulum functions in synthesis of
Lipids
Which of the following groups of organelles contain acid hydrolases, catalase, and detoxifying enzymes for drugs, respectively?
Lysosome, peroxisome, smooth endoplasmic reticulum
In which of the following properties are the archaea more like eukaryotes than the bacteria?
Translation initiation
Describe the different functions of vacuoles
-Food vacuoles are formed by phagocytosis -Contractile vacuoles, found in many freshwater protists, pump excess water out of cells -Central vacuoles, found in many mature plant cells, hold organic compounds and water
Describe the main limitations on cell size
-The requirement for adequate surface area relative to volume -The rates at which molecules can diffuse -The need to maintain adequate local concentrations of substances required for necessary cellular functions
The size range of most plant and animal cells is
10 - 100 μm
The methanobacteria, halobacteria, and sulfobacteria are included in which domain?
Archaea
Which of the following is characteristic of eukaryotic cells?
Membrane-bounded nucleus
Describe the main distinction between the two main types of cells
Membrane-bounded nucleus of eukaryotic cells
Which of the following organelles is not generally found in animal cells?
Central vacuole
Which molecules do not normally cross the nuclear membrane?
DNA
Which of the following processes would be most likely to occur in the Golgi complex?
Glycosylation of proteins
When the size of a cell increases, the surface area/volume ratio
Increases
Describe the main function of the mitochondria and the chloroplasts
Mitochondria: -changes energy from one form to another -sites of cellular respiration Chloroplasts: -changes energy from one form to another -found in plants and algae and are the sites of photosynthesis
Name the components of the endomembrane system
Nucleus, ER (rough and smooth), golgi apparatus, endosomes, lysosomes, and vacuoles
Which of the following organelles has only a single membrane around it?
Peroxisome
Which of the following is true of plant cells?
Plant cells may contain chloroplasts
Explain the endosymbiotic theory
Suggests that an early ancestor of eukaryotes engulfed an oxygen-using nonphotosynthetic prokaryotic cell. The engulfed cell formed a relationship with the host cell, becoming an endosymbiont. The endosymbionts evolved into mitochondria At least one of these cells may have then taken up a photosynthetic prokaryote, which evolved into a chloroplast
Which of the following is a characteristic common to all ribosomes from organisms of the three domains of life?
contain proteins and rRNA and catalyze protein synthesis.
