Cells

Question 1

What are the three components of the original Cell Theory?

Answer 1

1. All organisms are made of one or more cells.
2. The cell is the basic unit of life in all living things.
3. All cells come from preexisting cells.

Question 2

Who discovered cells and when?

Answer 2

Robert Hooke in 1665 while observing cork; he described them as tiny boxes.

Question 3

Who observed single-celled organisms in pond water?

Answer 3

Anton van Leeuwenhoek in 1673.

Question 4

Who concluded that all plant parts are made of cells?

Answer 4

Matthias Schleiden in 1838.

Question 5

Who stated that all animal tissues are composed of cells?

Answer 5

Theodor Schwann in 1839.

Question 6

Who concluded that cells arise from preexisting cells?

Answer 6

Rudolf Virchow in 1858.

Question 7

What is Spontaneous Generation and who disproved it?

Answer 7

The idea that life arises from non-living matter; Louis Pasteur disproved it.

Question 8

List 4 additions of the Modern Cell Theory.

Answer 8

1. Cells have DNA passed during division.
2. Cells share chemical composition and metabolism.
3. All functions occur inside cells.
4. Cell activity is due to organelles.

Question 9

What is a cell?

Answer 9

The smallest living unit of an organism; microscopic in size.

Question 10

What is the difference between prokaryotic and eukaryotic cells?

Answer 10

Prokaryotes lack a nucleus; eukaryotes have a nucleus and organelles.

Question 11

What is the function of the plasma membrane?

Answer 11

It encloses the cell contents and regulates movement in and out of the cell.

Question 12

What is the fluid mosaic model?

Answer 12

Describes the dynamic nature of the cell membrane made of phospholipids and proteins.

Question 13

What do membrane proteins do?

Answer 13

Transport molecules, recognize signals, identify cells, and catalyze reactions.

Question 14

What is the function of the cell wall?

Answer 14

Provides support; in plants (cellulose), fungi (chitin), and some protists.

Question 15

What is the cytoplasm?

Answer 15

Fluid inside the cell containing organelles, cytosol, and storage substances.

Question 16

What does the cytoskeleton do?

Answer 16

Provides support, anchors organelles, and assists in movement.

Question 17

What is the function of cilia and flagella?

Answer 17

Cilia move substances; flagella move cells (e.g., sperm).

Question 18

What is the nucleus?

Answer 18

Control center of the cell; contains DNA and nucleolus.

Question 19

What does the nucleolus do?

Answer 19

Synthesizes RNA and forms ribosomes.

Question 20

What is the difference between rough and smooth ER?

Answer 20

Rough ER has ribosomes and makes proteins; smooth ER builds lipids and carbohydrates.

Question 21

What is the function of the Golgi apparatus?

Answer 21

Modifies, packages, and ships molecules via vesicles.

Question 22

What do lysosomes do?

Answer 22

Digest old cell parts and invaders.

Question 23

What are vacuoles?

Answer 23

Storage sacs for water, food, and wastes; more common in plants.

Question 24

What is the function of mitochondria?

Answer 24

Break down fuel to produce ATP through cellular respiration.

Question 25

What do chloroplasts do?

Answer 25

Capture solar energy to produce glucose through photosynthesis.

Question 26

What is the endosymbiotic theory?

Answer 26

Eukaryotic cells evolved from symbiotic relationships between primitive cells and bacteria.

Question 27

What is the function of the cell membrane?

Answer 27

Separates cell from environment; regulates what enters/exits; maintains homeostasis.

Question 28

What is passive transport?

Answer 28

Movement of molecules from high to low concentration without energy.

Question 29

What is diffusion?

Answer 29

Movement of small particles across a membrane from high to low concentration.

Question 30

What is osmosis?

Answer 30

Diffusion of water through a selectively permeable membrane.

Question 31

What is facilitated diffusion?

Answer 31

Movement of large molecules like glucose via protein channels.

Question 32

What happens in a hypertonic solution?

Answer 32

Water exits the cell, causing it to shrink.

Question 33

What happens in a hypotonic solution?

Answer 33

Water enters the cell, causing it to swell or burst.

Question 34

What happens in an isotonic solution?

Answer 34

Water moves in and out equally; cell stays the same.

Question 35

What is active transport?

Answer 35

Movement of molecules from low to high concentration using energy.

Question 36

What are protein pumps?

Answer 36

Proteins that use energy to move substances against the concentration gradient.

Question 37

What is endocytosis?

Answer 37

Process by which large molecules are engulfed into the cell.

Question 38

What is exocytosis?

Answer 38

Process by which large molecules or waste are expelled from the cell.

Question 39

Give an example of endocytosis.

Answer 39

White blood cells engulfing bacteria.