Chapter 3- Cell Structure

Question 1

What are the two statements that are comprised in the Cell Theory?

Answer 1

• The cell is the building block of all organisms

* Cells come from preexisting cells

Question 2

Characteristics of prokaryotes

Answer 2

• Simple cells
• Do not contain a nucleus or many cell organelles
• Monera: the only known kingdom to consist of prokaryotes

Question 3

Characteristics of eukaryotes

Answer 3

• Complex cells
• Have a nucleus and many organelles
• Contains internal membranes
• Each organelle carries out a certain function
• More efficient than prokaryotes

Question 4

Differences between animal and plant cells

Answer 4

Plant cells have: 
•Cell wall
•Chloroplasts
•Large, central vacuole
•Plasmodesmata

Animal cells have:
•Lysosomes
•Centrioles
•Flagella

Question 5

Characteristics/Functions of the nucleus

Answer 5

• Have a nuclear envelope, chromatin, nuclear pores and a nucleolus
• Control centre for the cell’s functions
• Nucleolus: site where ribosomal RNA is produced/stored, involved in interactions between the nucleus and the cytoplasm
• Chromatin: hereditary material of the cell, condenses to form chromosomes during cell division, composed of protein and DNA
• Humans have 46 chromosomes

Question 6

Function of cytoplasm

Answer 6

Contains and supports all the cell’s organelles

Question 7

Characteristics/Function of the cell membrane

Answer 7

• Composed of phospholipids and proteins

* Allows movement of materials in and out of the cell

Question 8

Function/Differences of the Endoplasmic Reticulum

Answer 8

•Smooth: moves molecules from one area to another, responsible for lipid synthesis and detoxifying the cell
•Rough: attached with ribosomes, produce large amounts of protein for export from the cell
Both have the ability for sections to break free and create vesicles

Question 9

Characteristics/Function of the Golgi apparatus

Answer 9

• Stack of a half a dozen or more flattened sacs
• Protein-filled vesicles from the E.R. are received at one end, and then sorted and packaged in vesicles at the other side
• Vesicles move to different locations in the cell
• Centre of manufacturing, warehousing, sorting and shipping

Question 10

Function of Vacuoles

Answer 10

•Storage area for water, nutrients, and wastes

Question 11

Function of Vesicles

Answer 11

•Storage site for various kinds of molecules

Question 12

Function of Lysosomes

Answer 12

•Contain powerful enzymes used to digest substances entering the cell or organelles that are of no further use

Question 13

Characteristics/Function of ribosomes

Answer 13

• Contain rRNA and protein subunits

* Sites of protein synthesis

Question 14

Characteristics/Function of the mitochondria

Answer 14

• Burns glucose to produce ATP
• Performs cellular respiration in the inner membrane
• Considered the powerhouse of the cell

Question 15

Characteristics/Function of the cytoskeleton

Answer 15

• Provides internal structure to maintain the cell’s shape, anchor the organelles and allow them to move when appropriate
• Composed of microfilaments and microtubules

Question 16

Characteristics/Function of cilia/flagella

Answer 16

• hair-like projections used for locomotion by many unicellular organisms
• Flagella can be much longer

Question 17

How do the lysosome and the cytoskeleton rely on the ribosomes?

Answer 17

The ribosomes synthesize the enzymes of the lysosomes and the proteins of the cytoskeleton

Question 18

How do the other organelles rely on the nucleus?

Answer 18

The DNA in the nucleus sends genetic messages of the information for the proteins

Question 19

How do the other organelles rely on the mitochondria?

Answer 19

All the processes performed by the different organelles require ATP, which is produced by the mitochondria