1. a beam of electrons
2. high temperatures
3. radioactive isotopes
4. special stains

1. cell
2. organism
3. organ
4. tissue

1. All living organisms are made of cells.
2. All cells contain DNA that they pass on to daughter cells.
3. All cells depend on their surroundings to provide energy.
4. All cells have a nucleus.

Which of the following could most effectively be visualized with a scanning electron microscope?

1. cells swimming in a drop of pond water
2. details of structures inside cells
3. a three-dimensional view of the surface of a membrane
4. the movement of molecules inside the cell

Who was the first to clearly identify and name individual cells?

1. Anton van Leeuwenhoek
2. Matthias Schleiden
3. Robert Hooke
4. Theodor Schwann

1. Animal and plant cells have nuclei and organelles.
2. Non-living material cannot give rise to living organisms.
3. Prokaryotic and eukaryotic cells are surrounded by a plasma membrane.
4. Viruses replicate.

1. cell division
2. diffusion
3. flagellar motion
4. ribosomes

When bacteria lack fimbriae, what are they less likely to do?

1. adhere to cell surfaces
2. retain the ability to divide
3. swim through bodily fluids
4. synthesize proteins

1. Both cells have a nucleus but prokaryotic cells lack cytoplasm.
2. Both cells have cytoplasm but prokaryotic cells lack a nucleus.
3. Both cells have DNA but prokaryotic cells lack a cell membrane.
4. Both cells have a cell membrane but prokaryotic cells lack DNA.

Eukaryotic cells contain complex organelles that carry out their chemical reactions. Prokaryotes lack many of these complex organelles, although they have a variety of unique structures of their own. However, most prokaryotic cells can exchange nutrients with the outside environment faster than most eukaryotic cells. Why is this so?

1. Most prokaryotic cells are smaller, and have a higher surface-to-volume ratio, than eukaryotic cells.
2. Most prokaryotic cells are larger, and have a higher surface-to-volume ratio, than eukaryotic cells.
3. Most prokaryotic cells are smaller, and have a lower surface-to-volume ratio, than eukaryotic cells.
4. Prokaryotic cells are larger, and have a lower surface-to-volume ratio, than eukaryotic cells.

1. lysosomes
2. ribosomes
3. nucleolus
4. nucleus

Peroxisomes got their name because hydrogen peroxide is

1. a cofactor for the organelles' enzymes
2. incorporated into their membranes
3. produced during their oxidation reactions
4. used in their detoxification reactions

1. nuclei
2. peroxisomes
3. ribosomes
4. vacuole

1. mitochondrion
2. nucleus
3. ribosomes
4. centrosomes

1. plasma membrane
2. chloroplast
3. nucleoid
4. ribosome

1. in the centriole
2. only in the mitochondria
3. in the mitochondria and the nucleus

1. a cell that secretes enzymes
2. a cell that destroys pathogens
3. a cell that makes steroid hormones
4. a cell that engages in photosynthesis

1. synthesis of the protein on the ribosome; modification in the Golgi apparatus; packaging in the endoplasmic reticulum; modification in the vesicle
2. synthesis of the protein on the lysosome; modification in the Golgi; packaging in the vesicle; distribution in the endoplasmic reticulum
3. synthesis of the protein on the ribosome; modification in the endoplasmic reticulum; tagging in the Golgi; distribution via the vesicle
4. synthesis of the protein on the lysosome; packaging in the vesicle; distribution via the Golgi; modification in the endoplasmic reticulum

1. endoplasmic reticulum
2. Golgi apparatus
3. lysosome
4. mitochondrion

1. intermediate filaments and microtubules
2. microfilaments and intermediate filaments
3. microfilaments and microtubules
4. only intermediate filaments

1. intermediate filaments and microtubules
2. microfilaments and intermediate filaments
3. microfilaments and microtubules
4. only intermediate filaments

1. intermediate filaments
2. microfilaments
3. microtubules

1. desmosomes
2. gap junctions
3. plasmodesmata
4. tight junctions

1. gaps in the cell wall of plants
2. protein complexes that form channels between cells
3. tight, rivet-like regions in the membranes of adjacent cells
4. a tight knitting of membranes

1. actin
2. collagen
3. myosin
4. tubulin

Which of the following molecules is typically found in the extracellular matrix?

1. nucleic acids such as DNA
2. peptidoglycans
3. cellulose
4. proteoglycans