Tour of the Cell

Question 1

all organisms are made up of?

Answer 1

cells

Question 2

what are some examples of single celled organisms?

Answer 2

bacteria and archaea

Question 3

what are some examples of multicellular organisms?

Answer 3

fungi, plants, animals, protists

Question 4

what is the cell theory?

Answer 4

1. every living organism is made up of one or more cells.
2. the smallest living organisms are single cells and cells are the functional units of multicellular organisms.
3. all cells arise from preexisting cells.

Question 5

what are the two types of cells?

Answer 5

prokaryotic and eukaryotic cells

Question 6

some information about prokaryotic cells?

Answer 6

• do not have a nucleus
• small
• lack other membrane bound organelles

Question 7

some information about eukaryotic cells?

Answer 7

• has a nucleus
• larger
• have other membrane bound organelles

Question 8

size of cells: prokaryotic vs eukaryotic cells?

Answer 8

prokaryotic: 1-5um
eukaryotic: 10-100um

Question 9

do larger organisms have larger cells?

Answer 9

no they just have more cells.

Question 10

basic components of any cell?

Answer 10

ribosomes, genetic material, plasma membrane, cytoplasm

Question 11

all organisms can be placed into one of three?

Answer 11

domains: bacteria, archaea, eukarya

Question 12

how are cells studied?

Answer 12

with the use of microscopes

Question 13

the most commonly used microscope in the lab is?

Answer 13

light microscope

Question 14

what are the 4 light microscopes that are commonly used?

Answer 14

• bright field microscope
• dark field microscope
• phase contrast microscope
• fluorescence microscope

Question 15

most modern microscopes are?

Answer 15

compound microscopes meaning they use several lenses in combination to enlarge an image.

Question 16

what are bright field microscopes useful for?

Answer 16

• looking at dead stained cells
• one will see a dark object on a light background

Question 17

which microscopes allow one to see living organisms?

Answer 17

darkfield and phase contrast

Question 18

what are electron microscopes?

Answer 18

electron microscopes use electrons as the source of illumination.
1. transmission electron microscope
2. scanning electron microscope

Question 19

what is the transmission electron microscope used for?

Answer 19

forms an image from electrons transmitted from the specimen. it is used to look at INTERNAL STRUCTURES

Question 20

what is the scanning electron microscope used for?

Answer 20

forms an image from electrons that are deflected from the specimens outer surface.
it is used to look at the SURFACE TOPOLOGY OF A CELL: gives 3D SHAPE

Question 21

strength and weakness of electron microscope?

Answer 21

strength: great magnification
weakness: cant look at living specimens, specimen prep is time consuming and difficult, needs a lot of technical expertise, machine is very large and expensive.

Question 22

what is an organelle?

Answer 22

a membrane bound structure with a specialized function within the cell.
examples: golgi apparatus.

Question 23

what is the endomembrane system?

Answer 23

a collection of membranes inside and surrounding the cell.

Question 24

what are some components of the endomembrane system?

Answer 24

nuclear envelope, endoplasmic reticulum, golgi apparatus, lysosomes, plasma membrane, vesicles, vacuoles.

Question 25

the membranes of the endomembrane system are related by?

Answer 25

direct physical continuity or by the transfer of content via vesicles.

Question 26

what structures are found in animal cells but not plant cells?

Answer 26

flagellum, centrioles, lysosomes

Question 27

what structures are found in plant cells but not animal cells?

Answer 27

chloroplast, central vacuole, cell wall

Question 28

animal cells do not have?

Answer 28

a cell wall.

Question 29

what do animal cells have instead of a cell wall?

Answer 29

they have a plasma membrane and outside of the plasma membrane is the extracellular matrix.

Question 30

what does the extracellular matrix consist of?

Answer 30

• protein fibers
• the most abundant protein found in the ecm is collagen
• plays a role in structural support

Question 31

collagen is embedded in?

Answer 31

a network of proteoglycan complexes

Question 32

what is a proteoglycan?

Answer 32

protein with many carbohydrate chains attached.

Question 33

what does a proteoglycan complex consist of?

Answer 33

a proteoglycan complex consists of many proteoglycans noncovalently attached to a single polysaccharide molecule.

Question 34

collagen is embedded in?

Answer 34

a network of proteoglycan complexes

Question 35

what are the functions of the ecm?

Answer 35

• provides structural support
• helps to keep individual cells in place
• keeps adjacent cells in contact with one another
• plays a role in communicating with the cell

Question 36

plant cell communication?

Answer 36

plant cells have cell walls surrounding them, they have plasmodesmata which are channels that connect the cytoplasm of two plant cells.

Question 37

animal cell communication?

Answer 37

in animal cells, communication occurs through gap junctions. gap junctions consist of specialized membrane proteins that surround a pore thereby allowing certain molecules to pass through.