Chapter 3- Cells

Question 1

What is a cell?

Answer 1

The smallest unit of life that can function independently.

Question 2

What are the components of early cell theory?

Answer 2

1) All organisms are made of one or more cells.
2) The cell is the fundamental unit of life.
3) All cells come from preexisting cells.

Question 3

What are the newer ideas of the modern cell theory?

Answer 3

1) All cells have the same basic chemical composition.

2) All cells use energy.

Question 4

What does TEM stand for?

Answer 4

Transmission electron microscope- a very powerful tool for seeing internal cell structures.

Question 5

What does SEM stand for?

Answer 5

Scanning electron microscope- a very powerful tool that reveals details on cell surfaces.

Question 6

All cells have what?

Answer 6

Genetic material, ribosomes, cytoplasm, and a cell membrane.

Question 7

What are Prokaryotes?

Answer 7

The most ancient forms of life. They are small, simple in structure, and lack a nucleus.

Question 8

What are two different domains in prokaryotes?

Answer 8

Bacteria and Archaea.

Question 9

What are Eukaryotes?

Answer 9

Evolved billions of years after prokaryotes, they are larger and more complex, and contain many internal parts such as the nucleus and membranous organelles.

Question 10

What are some domains found within Eukaryotes?

Answer 10

Protists, fungi, plants, and animals.

Question 11

What are bacteria?

Answer 11

They are prokaryotic, lack membrane-bounded organelles, and their ribosomes and DNA are freely in the cytoplasm.

Question 12

What are animal cells?

Answer 12

Eukaryotic and they have many different membrane-bounded organelles.

Question 13

What are plant cells?

Answer 13

They are also eukaryotic, but they also have chloroplasts, cell walls, and large central vacuole.

Question 14

What is the main function of a cell membrane?

Answer 14

Forms a barrier between the cell and the outside world.

Question 15

Where are phospholipids found?

Answer 15

They make up cell membranes.

Question 16

What are phospholipids?

Answer 16

Amphipathic- meaning there are polar and non polar regions in the same molecule.

Question 17

What is a hydrophilic head?

Answer 17

Polar bonds, which are attracted to water.

Question 18

What is a hydrophobic tail?

Answer 18

Non polar bonds, which repel water.

Question 19

When were cells discovered?

Answer 19

They were discovered after the microscope was invented in the mid 1800’s.

Question 20

What does a bacteria contain inside of it?

Answer 20

They contain a cell wall, flagellum, ribosomes, cell membranes, and cytoplasm.

Question 21

What are the three major components of Cytoskeletons?

Answer 21

Microfilaments, intermediate filaments, and microtubules.

Question 22

What are microfilaments for?

Answer 22

They are needed for cell contraction and changes in cell shape.

Question 23

What are intermediate filaments for?

Answer 23

They form a strong scaffold for mechanical strength.

Question 24

What are microtubules for?

Answer 24

Microtubules act as trackways for moving organelles and vesicles.

Question 25

Plant cells communicate through what?

Answer 25

Plasmodesmata

Question 26

What are plasmodesmata?

Answer 26

Plasmodesmata are channels that pass through the plant cell wall.

Question 27

What is the primary reasoning behind cells sticking together?

Answer 27

Cells stick together in multicellular organisms to keep in constant communication with each other.

Question 28

How do animal cells communicate with each other?

Answer 28

They communicate through gap junctions.

Question 29

What are gap junctions?

Answer 29

The proteins form tunnels through the membranes of two neighboring cells.

Question 30

What are tight junctions in animal cells?

Answer 30

In tight junctions, proteins fuse the membranes of adjacent animal cells together.

Question 31

What is the endomembrane system’s primarily function?

Answer 31

To move molecules around in a cell.