ch. 4 cell structure

Question 1

who discovered cells and when?

Answer 1

Hooke, 1660’s

Question 2

who proposed the cell theory? when?

Answer 2

Schneider and Schwann, 1830’s

Question 3

as a cell increases in size, volume increases ___x faster than the surface area

Answer 3

10

Question 4

what three structures do all cells have in common?

Answer 4

genetic material, cytoplasm, plasma membrane

Question 5

What is the function of prokaryotic cell walls?

Answer 5

they protect the cell and maintain cell shape

Question 6

what are prokaryotic cell walls made of?

Answer 6

peptidoglycan (bacteria) or similar substances (archaea)

Question 7

what does it mean if a prokaryotic cell wall is gram negative?

Answer 7

they are surrounded by a thin peptidoglycan cell wall which is surrounded by an outer-membrane

Question 8

what does it mean if a prokaryotic cell wall is gram positive?

Answer 8

they lack an outer membrane but are surrounded by layers of peptidoglycan many times thicker than is found in the Gram-negatives

Question 9

where can you find simple flagella?

Answer 9

in some prokaryotic cells

Question 10

what kind of motion does the simple flagella make to move the cell?

Answer 10

rotary motion

Question 11

what surrounds the nucleus?

Answer 11

a nuclear envelope

Question 12

what is the nuclear envelope composed of?

Answer 12

2 phospholipid bilayers

Question 13

what is the function of ribosomes?

Answer 13

they are the site of protein synthesis

Question 14

what are ribosomes composed of?

Answer 14

rRNA and proteins

Question 15

where are ribosomes found?

Answer 15

in the cytoplasm and attached to membranes

Question 16

what parts of the cell make up the endomembrane system?

Answer 16

nuclear membrane, ER, golgi, secretory vesicles

Question 17

what is the endomembrane system?

Answer 17

a semi-continuous system of interconnected membranes

Question 18

What are the functions of the rough ER?

Answer 18

creates a network of channels throughout the cytoplasm, synthesis of proteins that will be secreted and then sent to lysosomes or the plasma membrane

Question 19

What are the functions of smooth ER

Answer 19

synthesis of membrane lipids, calcium storage, detoxification of foreign substances

Question 20

what are the golgi apparatus?

Answer 20

flattened stacks of interconnected membranes that package and distribute materials to different parts of the cell and synthesize cell wall components

Question 21

what do lysosomes contain?

Answer 21

digestive enzymes

Question 22

what is the function of lysosomes?

Answer 22

they break down macromolecules for recycling of foreign matter that the cell has engulfed

Question 23

what are microbodies?

Answer 23

vesicles containing enzymes

Question 24

what are glyoxysomes?

Answer 24

microbodies in plants that contain enzymes for converting fats to carbs

Question 25

what are peroxisomes?

Answer 25

microbodies that contain oxidative enzymes and catalase

Question 26

are vacuoles membrane-bound?

Answer 26

yes

Question 27

where can contractile vacuoles be found?

Answer 27

in some protists

Question 28

what is the function of mitochondria?

Answer 28

they contain oxidative metabolism enzymes fir transferring energy from macromolecules to ATP

Question 29

what do the two mitochondria membranes look like?

Answer 29

a smooth outer membrane and a folded inter membrane with layers called cristae

Question 30

where is the matrix in the mitochondria?

Answer 30

within the inner membrane

Question 31

what are thylakoids?

Answer 31

membrane sacs within the inner membrane

Question 32

what is the cytoskeleton made up of

Answer 32

protein fibers

Question 33

what is the purpose of the cytoskeleton?

Answer 33

supports the shape of the cell, keeps organelles in fixed locations, helps move materials within the cell

Question 34

what are the three cytoskeleton fibers?

Answer 34

actin filaments, microtubules, and intermediate filaments

Question 35

what are actin filaments responsible for?

Answer 35

cellular contractions, crawling, “pinching”

Question 36

what is the purpose of microtubules?

Answer 36

to provide organization to the cell and move materials within the cell

Question 37

what is the function of intermediate filaments?

Answer 37

they provide structural support

Question 38

what makes up flagella and cilia?

Answer 38

microtubules

Question 39

how is the cell movement “crawling” accomplished?

Answer 39

with actin filaments and myosin

Question 40

what is the structure of cilia and flagella?

Answer 40

“9 + 2” structure

Question 41

what is a “9 + 2” structure?

Answer 41

9 pairs of microtubules surrounded by two central microtubules

Question 42

what drives the flagella and cilia?

Answer 42

proton gradients

Question 43

what are some extra cellular structures?

Answer 43

cell walls and extra cellular matrix

Question 44

what type of cells contain cell walls?

Answer 44

plants, fungi, and some protists

Question 45

what is the CHO in the cell wall of plants and protists?

Answer 45

cellulose

Question 46

what is the CHO in the cell walls of fungi?

Answer 46

chitin

Question 47

what is chitin?

Answer 47

a glycoprotein

Question 48

what is the extra cellular matrix composed of?

Answer 48

glycoproteins and fibrous proteins like collagen

Question 49

how might the extracellular matrix be connected to the cytoplasm?

Answer 49

with integrin proteins present in the plasma membrane

Question 50

how many cells do humans have?

Answer 50

over a trillion

Question 51

what is endosymbiosis?

Answer 51

the theory that eukaryotic organelles evolved through a symbiotic relationship where one cell engulfed another (ex: mitochondria and chloroplasts)