Ch 6: A Tour of the Cell

Question 1

What is a cell?

Answer 1

basic structural and functional units of every organism

Question 2

What are the two types of cells?

Answer 2

prokaryotic and eukaryotic

Question 3

What is the domain of prokaryotic cells?

Answer 3

bacteria and archaea

Question 4

What is the domain of eukaryotic cells?

Answer 4

domain eukarya–protists, fungi, animals, and plants

Question 5

How do light microscopes work?

Answer 5

visible light is passed through the specimen and then through glass lenses and the lenses refract light in such a way that the image of the specimen is magnified

Question 6

What are three important parameters in microscopy?

Answer 6

magnification, resolution, and contrast

Question 7

What can you see with a light microscope?

Answer 7

frog eggs, human egg, most plant and animal cells, nucleus, most bacteria, mitochondria, smallest bacteria, viruses, and ribosomes

Question 8

What can you see with a electron microscope?

Answer 8

most plant and animal cells, nucleus, most bacteria, mitochondria, smallest bacteria, viruses, ribosomes, proteins and lipids

Question 9

True or false: the resolution of standard light microscopy is too low to study organelles

Answer 9

true

Question 10

What is a organelle?

Answer 10

the membrane-enclosed structures in eukaryotic cells

Question 11

What is the average length of a cell?

Answer 11

most cells are between 1 and 100 μm in diameter

Question 12

What are electron microscopes (EMs) used for?

Answer 12

they are used to study subcellular structures

Question 13

How do scanning electron microscopes (SEMs) work?

Answer 13

they focus a beam of electrons onto the surface of a specimen, providing images that look 3-D

Question 14

How do transmission electron microscopes (TEMs) work?

Answer 14

they focus a beam of electrons through a specimen

Question 15

Transmission electron microscopes are used to mainly study:

Answer 15

the internal structure of cells

Question 16

What is the disadvantage of EMs?

Answer 16

it kills cells

Question 17

What is cytology?

Answer 17

the study of cell structure

Question 18

What is biochemistry?

Answer 18

the study of the chemical processes (metabolism) of cells

Question 19

What is cell fractionation?

Answer 19

a technique for studying cell structure and function, takes cells apart and separates major organelles and other subcellular structures

Question 20

What basic features are shared between cells?

Answer 20

bounded by a plasma membrane/cell membrane, cytosol, chromosomes, and ribosomes

Question 21

Where is DNA in Eukaryotic cells?

Answer 21

most of the DNA is in the nucleus, (bounded by a double membrane)

Question 22

Where is DNA in prokaryotic cells?

Answer 22

the DNA is in a region that is not membrane-enclosed, called the nucleoid

Question 23

What does eukaryotic mean?

Answer 23

“true nucleus”

Question 24

What does prokaryotic mean?

Answer 24

“before nucleus”

Question 25

What is a cytoplasm?

Answer 25

in eukaryotic cells, this term refers only to the region between the nucleus and the plasma membrane

Question 26

What is an organelle?

Answer 26

structures with special form and function and are membrane-bound

Question 27

Where are organelles in eukaryotic cells?

Answer 27

suspended in cytoplasm

Question 28

Where are organelles in prokaryotic cells?

Answer 28

absent in almost all prokaryotic cells

Question 29

Which cells are generally bigger? Eukaryotic or Prokaryotic?

Answer 29

eukaryotic cells

Question 30

What is a plasma membrane?

Answer 30

a selective barrier, allows passage of certain molecules

Question 31

Cellulare size:

Answer 31

smaller cell has a greater ratio of surface area to volume, larger organisms do not have larger cells they have more cells

Question 32

Where is the nuclear envelope?

Answer 32

it encloses the nucleus and has a double membrane (lipid bilayer)

Question 33

What is the nuclear envelope perforated by?

Answer 33

pore structures

Question 34

The pore complex regultes:

Answer 34

the movement of proteins, RNAs, and macromolecules

Question 35

Where is the nuclear lamina?

Answer 35

the netlike lamina lines the inner surface of the nuclear envelope

Question 36

What are chromosomes?

Answer 36

structures that carry genetic information

Question 37

What are histones?

Answer 37

small proteins associated with one long DNA molecule

Question 38

What are chromatins?

Answer 38

the complex of DNA and proteins making up chromosomes

Question 39

What is the role of nucleolus?

Answer 39

they play a role in controlling cell division and synthesizing rRNA and ribosome subunits

Question 40

What are ribosomes?

Answer 40

complexes made of ribosomal RNAs and proteins, are the cellular components that carry out protein synthesis, and they are not membrane-bounded and thus are not considered organ

Question 41

What is the endomembrane system?

Answer 41

synthesis/transport of proteins, metabolism and movement of lipids, and detoxification of poisons

Question 42

Membrane-bound organelles in the endomembrane system:

Answer 42

nuclear envelope, the endoplasmic reticulum, the golgi apparatus, lysosomes, various kinds of vesicles and vacuoles, and the plasma membrane

Question 43

How are the membranes of the endomembrane system related?

Answer 43

either through direct physical continuity or by the transfer of membrane segments as tiny vesicles

Question 44

What are vesicles?

Answer 44

sacs made of membrane

Question 45

What is the endoplasmic reticulum?

Answer 45

a network of membranous tubules and sacs called cisternae that accounts for more than half of the total membrane

Question 46

Whate are the two types of ER?

Answer 46

smooth ER and rough ER

Question 47

What is smooth ER?

Answer 47

the outer surface lacks ribosomes

Question 48

What is rough ER?

Answer 48

studded with ribosomes on the outer surface and appears rough

Question 49

What is the function of smooth ER?

Answer 49

synthesis of lipids, metabolism of carbohydrates, detoxification of drugs and poisons, and storage of calcium ions

Question 50

What is the function of rough ER?

Answer 50

rough ER us a membrane factory for the cell; the ribosomes attached to rough ER secrete proteins used by the cell

Question 51

What is the most common secretory protein for rough ER?

Answer 51

glycoproteins

Question 52

What is the structure of a glycoprotein?

Answer 52

proteins with carbohydrates covalently bonded to them

Question 53

What are transport vesicles?

Answer 53

vesicles in transit from one part of the cell to another