Chapter 5 Cell Structure, Form And Function

Question 1

What are the comon features found in all cells?

Answer 1

1. Plasma membrane
2. Cytoplasm
3. Chromosomes
4. Ribosomes
5. Cytoskeleton

Question 2

What is diffusion?

Answer 2

Diffusion is the movement of molecules from an area of high to low concentration. Eventually, the particles all reach equilibrium where the concentration of substances are the same.

Question 3

What is osmosis?

Answer 3

Water passes through a semipermeable membrane from an area of low solute to high solute concentration area.

Question 4

What kind of molecules can move by simple diffusion?

Answer 4

Small, hydrophobic molecules.

Question 5

What is facilitated diffusion?

Answer 5

Transport proteins speed passive movement of hydrophilic molecules across a plasma membrane.

Question 6

What is active transport?

Answer 6

The movement of molecules that moce against their concentration gradient. This movement requires ATP.

Question 7

Define hypotonic solution.

Answer 7

Low solute concentration.

Question 8

Define hypertonic solution.

Answer 8

High solute concentration.

Question 9

Define isotonic solution.

Answer 9

Same solute concentration in and outside the cell.

Question 10

Describe the movement of water in a cell

Answer 10

Water moves from an area of low solute concentration to high solute concentration (always hypotonic to hypertonic.)

Question 11

What is turgur pressure?

Answer 11

The force exerted by water pressing against an object. Keeps plant cells rigid.

Question 12

What is the function of the nucleus?

Answer 12

Store the cells Genetic information and the site of RNA synthesis.

Question 13

What is the function of rough endoplasmic reticulum?

Answer 13

Associated with ribosomes which are the site of protein synthesis.

Question 14

What is the function of smooth endoplasmic reticulum?

Answer 14

Lacks ribosomes and is the site of lipid synthesis.

Question 15

What is the function of Golgi apparatus?

Answer 15

1. Chemically modify proteins and lipids.
2. Sort proteins and lipids.
3. Synthesize carbohydrates and attach them to proteins and lipids.

Question 16

What is the function of mitochondria?

Answer 16

Produce most of the ATP in the cell.

Question 17

What is the fuctiom of the plasma membrane?

Answer 17

Regulates the passage of materials into and out of the cell.

Question 18

Why is the cell membrane selectively permeable?

Answer 18

To control the flow of molecules, nutrients, and waste in and out of the cell.

Question 19

What is cytoskeleton and what is the function of cytoskeleton?

Answer 19

The cytoskeleton is a network of protein filaments and other associated proteins that provide the cell with an internal structural framework.

Question 20

What is the function of chloroplasts?

Answer 20

Enable plant cell to harness energy of sunlight to synthesize sugars.

Question 21

What are vacuoles and what is the function?

Answer 21

Vacuoles are water filled organelles that contribute to the structural rigidity of plants by maintaining turgir pressure against cell walls.

Question 22

What is the cell wall and function?

Answer 22

Cell wall is a rigid barrier composed of cellulose and it provides rigidity to plant cells.

Question 23

What is the function of lysosomes?

Answer 23

Specialized vesicles derived from golgi apparatus that contain hydrolotic enzymes that digest waste within animal cells.

Question 24

DNA can be found in what organelles in plant cells?

Answer 24

Nucleus, mitochondia, chloroplasts.

Question 25

Describe the endomembrane system.

Answer 25

Many organelles communicate with other organelles through physical contact or by the transfer of vesicles in order to synthesize and modify proteins and lipids to be shipped out of the cell.

Question 26

What is the function of organelles?

Answer 26

To physically separate different types of cell activities in the cytoplasm allowing for greater efficiency for cell activities by clustering enzymes that work together within an enclosed space.

Question 27

What does the golgi apparatus use to transport proteins?

Answer 27

Vesicles.

Question 28

What is glycosylation?

Answer 28

Type of modification that occurs in the GA. Sugars are covalently linked to lipids or to proteins as they move through the GA.

Question 29

How do macromolecules cross the cell membrane?

Answer 29

Via exocytosis and endocytosis.

Question 30

What is exocytosis?

Answer 30

Transport vesicles migrate to the membrane and release their content to the outside of the cell.

Question 31

What is endocytosis?

Answer 31

The cell takes in macromolecules by forming vesicles from the plasma membrane.

Question 32

What are not part of the endomembrane system?

Answer 32

Mitochondria and chloroplasts.

Question 33

What are the 3 types if cytoskeleton?

Answer 33

Microtubules, microfilents and intermediate filaments.

Question 34

What are the functions of microtubules?

Answer 34

1. Support the cell shape and give rigidity. 2. Separate replicated chromosome during cell division. 3. Act as track for movement of vesicles. 4. Found in cilia and flagella.

Question 35

Whya are the function of microfilaments?

Answer 35

1. Form an extensive network inside the plasma membrane to enforce the cell membrane and organize the membrane proteins. 2. Function as tracks for transport within the cell but involves the motor protein mysosin.

Question 36

What is the function of intermediate filaments?

Answer 36

Combine to form strong structures in the cell, providing mechanical strength.

Question 37

What are the differences between prokaryotic and eukaryotic cells.

Answer 37

Eukaryotes have membrane bounded organells and are much larger.

Question 38

What properties would impose upper limits on cell size?

Answer 38

In order for a cell to obtain everything it needs, it must have a high surface area to volume ratio sonit can efficiently take in nutrients and water for survival and also expel waste. If te cell is too large tham the SA to colume ratio would be too low and the cell would be unable to efficiently exchange these materials with its environment.

Question 39

What are cellular membranes composed of?

Answer 39

Fluid mosaics; Phopholipids and proteins.

Question 40

What molecule do animal cells have?

Answer 40

Cholesterol.

Question 41

Why are phospholipids called amphiprotic?

Answer 41

Have both hydrophobic and hydrophilic properties.

Question 42

What is the hydrophobic region of the phospholipid?

Answer 42

The fatty acid tail.

Question 43

What is the hydrophilic region of the phospholipid?

Answer 43

A polar group, a phoshate group and glycerol.

Question 44

What is the force between the fatty acid tails of phospholipids?

Answer 44

Van der waals forces.

Question 45

How can cholesterol increase or decrease membrane fluidity?

Answer 45

Cholesterol is known as membrane buffer. In cold temperatures cholesterol prevents phopholipids from Packing tightly and increases membrane fluidity. At normal temperatures cholesterol restrains movement of phopholipids and reduces membrane fluidity.

Question 46

What are 2 types of tranporter proteins?

Answer 46

Channels and carriers.

Question 47

What kind of molecules do transport proteins move acroos the membrane?

Answer 47

Ions and polar molecules.