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.