When viewing a specimen through a light microscope, scientists use ________ to distinguish the individual components of cells.
- a beam of electrons
- radioactive isotopes
- special stains
- high temperatures
The ________ is the basic unit of life.
- organism
- cell
- tissue
- organ
Prokaryotes depend on ________ to obtain some materials and to get rid of wastes.
- ribosomes
- flagella
- cell division
- diffusion
Bacteria that lack fimbriae are less likely to ________.
- adhere to cell surfaces
- swim through bodily fluids
- synthesize proteins
- retain the ability to divide
Which of the following is surrounded by two phospholipid bilayers?
- the ribosomes
- the vesicles
- the cytoplasm
- the nucleoplasm
Peroxisomes got their name because hydrogen peroxide is:
- used in their detoxification reactions
- produced during their oxidation reactions
- incorporated into their membranes
- a cofactor for the organelles’ enzymes
In plant cells, the function of the lysosomes is carried out by __________.
- vacuoles
- peroxisomes
- ribosomes
- nuclei
Which of the following is found both in eukaryotic and prokaryotic cells?
- nucleus
- mitochondrion
- vacuole
- ribosomes
Which of the following is not a component of the endomembrane system?
- mitochondrion
- Golgi apparatus
- endoplasmic reticulum
- lysosome
The process by which a cell engulfs a foreign particle is known as:
- endosymbiosis
- phagocytosis
- hydrolysis
- membrane synthesis
Which of the following is most likely to have the greatest concentration of smooth endoplasmic reticulum?
- a cell that secretes enzymes
- a cell that destroys pathogens
- a cell that makes steroid hormones
- a cell that engages in photosynthesis
Which of the following sequences correctly lists in order the steps involved in the incorporation of a proteinaceous molecule within a cell?
- synthesis of the protein on the ribosome; modification in the Golgi apparatus; packaging in the endoplasmic reticulum; tagging in the vesicle
- synthesis of the protein on the lysosome; tagging in the Golgi; packaging in the vesicle; distribution in the endoplasmic reticulum
- synthesis of the protein on the ribosome; modification in the endoplasmic reticulum; tagging in the Golgi; distribution via the vesicle
- synthesis of the protein on the lysosome; packaging in the vesicle; distribution via the Golgi; tagging in the endoplasmic reticulum
Which of the following have the ability to disassemble and reform quickly?
- microfilaments and intermediate filaments
- microfilaments and microtubules
- intermediate filaments and microtubules
- only intermediate filaments
Which of the following do not play a role in intracellular movement?
- microfilaments and intermediate filaments
- microfilaments and microtubules
- intermediate filaments and microtubules
- only intermediate filaments
Which of the following are found only in plant cells?
- gap junctions
- desmosomes
- plasmodesmata
- tight junctions
The key components of desmosomes are cadherins and __________.
- actin
- microfilaments
- intermediate filaments
- microtubules