Chapter 3: Cell Structure - Eukaryotes

Question 1

What microorganisms are eukaryotes? (3)

Answer 1

• algae
• fungi
• protozoa

Question 2

What higher organisms are eukaryotes? (2)

Answer 2

• plants
• animals

Question 3

How are eukaryotes different from prokaryotes? (3)

Answer 3

• larger and more complex than prokaryotes
• genetic material is housed in a nucleus
• contains membrane-bound organelles

Question 4

What does the eukaryotic cell membrane contain? (3)

Answer 4

• same basic structure as in prokaryotic cells
• phospholipids, proteins, and sterols

Question 5

What do the sterols in the cell membrane do?

Answer 5

• makes the membrane relatively rigid in comparison to bacteria

Question 6

What is the function of the cell wall?

Answer 6

• not all eukaryotes have a cell wall
• allows for endocytosis

Question 7

What is the structure of the eukaryotic cell wall? (2)

Answer 7

• simple in structure compared to bacteria
• cellulose (algae and plants)
• chitin (fungi)

Question 8

What is the cytoplasm?

Answer 8

• substance inside the plasma membrane but outside the nuclear membrane

Question 9

The cytoplasm has a complex internal structure called the _____.

Answer 9

cytoskeleton

Question 10

What is the cytoskeleton?

Answer 10

• protein filaments on the inside of the plasma mebrane

Question 11

What is the function of the cytoskeleton?

Answer 11

• provides support and shape
• transports substances through the cell

Question 12

What is different about ribosomes in eukaryotes than in bacteria? (2)

Answer 12

• larger and heavier
  80S

Question 13

What are microfilaments made of, and who do they interact with?

Answer 13

• made of strands of protein called actin
• interact with other strands of protein

Question 14

What are intermediate filaments?

Answer 14

• fibrous proteins organized into tough, ropelike assemblies that stabilize a cell’s structure and help maintain its shape

Question 15

What are microtubules?

Answer 15

• long, hollow cylinders made of many molecules of tubulin
• tubulin consists of two subunits, aplha and beta tubulin

Question 16

What are membrane-bound organelles?

Answer 16

• structure with specialized functions
• not present in bacteria

Question 17

Give 3 examples of membrane-bound organelles

Answer 17

• nucleus (holds genetic material)
• mitochondria (site of energy production)
• chloroplasts (site of photosynthesis in algae and plants)

Question 18

Do plants have mitochondria?

Answer 18

YES

Question 19

appendages external to the cell: What are flagella and Cilia? (2)

Answer 19

• long, flexible projections that contain protein and cytoplasm
• move in a whip-like fashion

Question 20

Appendages external to the cell: What is the function of flagella and cilia?

Answer 20

• used for motility and sweeping material past stationary cells

Question 21

What are general characteristics of PROKARYOTIC flagella? (3)

Answer 21

• made of protein subunits
• protrude through cell wall and cell membrane
• stiff, twirl like a propeller