Cell Structure + Function

Question 1

What are the basic principles of the cell theory?

Answer 1

1- All known living things are made up of one or more cells
2- All living cells arise from pre-existing cells by division
3- The cell is the fundamental unit of structure and function in all living organisms
4- The activity of an organism depends on the total activity of independent cells
5- Energy flow occurs within cells
6- Cells contain DNA which is found specifically in the chromosome and RNA found in the cell nucleus and cytoplasm
7- All cells are basically the same in chemical composition in organisms of similar species

Question 2

What are the two types of cells?

Answer 2

1) Prokaryotes: Unicellular organisms
-Two domains which are Bacteria and Archaea

2) Eukaryotes: multicellular organisms
-Animals, plants, fungi and algae

Question 3

Difference in size between prokaryotes and eukaryotes?

Answer 3

Prokaryotes: Small and typically between 0.1 and 5.0 micrometers in diameter

Eukaryotes: large and typically between 10 and 100 micrometers in diameter

Question 4

Difference in Nucleus between Prokaryotes and Eukaryotes?

Answer 4

Prokaryotes: No nuclear membrane or nucleoli.

Eukaryotes: True nucleus consisting of nuclear membrane and nucleoli

Question 5

Difference in membrane bound organelles between prokaryotes and eukaryotes?

Answer 5

Prokaryotes: Absent

Eukaryotes: Present such as lysosomes, golgi, ER, mitochondria and chloroplast

Question 6

Difference in flagella between prokaryotes and eukaryotes?

Answer 6

Prokaryotes: Structurally simple

Eukaryotes: Structurally complex

Question 7

What is the difference in cell wall between prokaryotes and eukaryotes?

Answer 7

Prokaryotes: Usually present and is chemically complex

Eukaryotes: When present is chemically simple

Question 8

Difference in cell wall between animal and plant cells?

Answer 8

Animal: Absent

Plant: Present and formed of cellulose

Question 9

Difference in shape between animal and plant cells?

Answer 9

Animals: Irregular indefinite shape

Plants: Fixed definite shape

Question 10

Difference in vacuoles between animal and plant cells?

Answer 10

Animals: one or more small vacuoles

Plant: oNe large central vacuole taking up to 90% of the cell volume

Question 11

Difference in centrioles between animal and plant cells?

Answer 11

Animal: centrioles are present in all animal cells

Plant: centrioles are only present in lower plant forms such as chlamydomonas

Question 12

Difference in chloroplast between animal and plant cells?

Answer 12

Animal: Absent

Plant: present

Question 13

Difference in plastids between animal and plant cells?

Answer 13

Animal: Absent

Plant: present

Question 14

Difference in flagella between animal and plant cells?

Answer 14

Both cells have a flagella in some of their cells such as mammalian sperm cells and sperm of bryophytes

Question 15

Difference in Cilia between animal and plant cells?

Answer 15

Animal: present

Plant: absent in most cells

Question 16

Difference in lysosomes in animal and plant cells?

Answer 16

Animal: lysosomes are found in the cytoplasm

Plant: lysosomes area;t usually present

Question 17

Difference in plasmodesmata between animal and plant cells

Answer 17

Animal: absent

Plant: present

Question 18

How to prepare a wet mount slide of onion epidermal cells?

Answer 18

1- cut onion to quarters
2- remove one of the fleshy scale leaves
3- shape the back of the leaf backward to expose the epidermis
4- peel off the thin epidermis layer
5- place the thin epidermis layer on a slide and spread it then add 2-3 drops of iodine
6- lower the coverslip gently with an angle

Question 19

How to prepare a wet mount slide of a geranium leaf?

Answer 19

1- take a fleshy geranium leaf
2- snap the leaf backward to expose the epidermis
3- peel off a thin layer of epidermis
4- place the peeled layer on the slide and add 2 drops of iodine
5- add coverslip with an angle

Question 20

How to prepare a wet mount slide of check epithelium cell?

Answer 20

1- add 2 to 3 drops of water to the slide
2- gently scrap the inside of your cheeks with the broad end of a toothpick
3- stir the scrapings into a drop of water onto the slide
4- lower the coverslip over your specimen gently with an angle to avoid air trapping
5- add 1-2 drops of methylene blue to the edge of the coverslip and draw the stain under the coverslip by touching filter paper to the opposite side of the coverslip