Cell Structures

Question 1

What are characteristics of living things?

Answer 1

1. Made up of cells. Unicellular (one cell, simple organism) or multicellular (many cells, complex organism)
2. Based on a universal genetic code.
3. Remain homeostasis (stable internal environment).
4. Metabolize (use material and energy to carry out life’s functions).
5. Reproduce. Asexual (one set of parental DNA) or sexual (two sets of parental DNA).
6. Grow and develop (change).
7. Respond to stimuli (environment).
8. Evolve

Question 2

Outline ‘Cell Theory.’

Answer 2

1. All living things are made up of one or more cells.
2. Cells are the smallest functional unit of all living things.
3. All cells come from pre-existing cells.

Question 3

All cells have three things, what are they?

Answer 3

1. Plasma membrane (lipid bilayer/ cell membrane)
2. Nucleus/ Nucleoid
3. Cytoplasm/ Cytosol (includes ribosomes)

Question 4

What is larger, plant cells or animal cells?

Answer 4

Plant Cells.

Question 5

What is the difference between the cytoplasm and the cytosol?

Answer 5

Cytoplasm is the entirety of the cell contained by the cell membrane. While, cytosol is the part of the cytoplasm not taken up by organelles.

Question 6

What are organelles?

Answer 6

Each cell contains many organelles, or small compartments in the cell that perform one or more specific function. Not all of the organelles are membrane bound.

Question 7

State whether the following organelles are present/absent in plant and animal cells.
Chloroplasts, Cell Wall, Large Central Vacuole, Polysaccharides, Centrioles.

Answer 7

Chloroplasts: present in plant cells, absent in animal cells.
Cell Wall: present in plant cells (rigid with cell membrane inside), absent in animal cells (plasma membrane flexible).
Large Central Vacuole: present in plant cells, absent or small in animal cells.
Polysaccharides: starch in plant cells, glycogen in animal cells.
Centrioles: absent in plant cells, present in animal cells.

Question 8

What is the function of the Nucleus?

Answer 8

Nucleus stores the genetic information of the cell in the form of chromosomes. It is surrounded by a double membrane and is the site of DNA replication and transcription.

Question 9

What is the function of the Cell Membrane?

Answer 9

Cell Membrane is a phospholipid bilayer that surrounds the cell. In controls what diffuses in/out (semi-permeable) and contains embedded proteins that serve many functions.

Question 10

What is the function of the Cytoplasm?

Answer 10

The cytoplasm is where chemical reactions take place.

Question 11

What is the function of Ribosomes?

Answer 11

Ribosomes are studded on the rough endoplasmic reticulum and are the site of protein synthesis.

Question 12

What is the function of the Rough Endoplasmic Reticulum?

Answer 12

The rough endoplasmic reticulum has ribosomes on its outer surface. Its role is to package proteins for secretion. It sends them in vesicles to the Golgi Apparatus.

Question 13

What is the function of the Vesicles?

Answer 13

Vesicles are small sacs made up of membrane that are used to transport materials within the cell.

Question 14

What is the function of the Golgi Apparatus?

Answer 14

The Golgi Apparatus processes the proteins that are received from the rough ER. Then it sends them in vesicles to the cell membrane.

Question 15

What is the function of Lysosomes?

Answer 15

Lysosomes contains enzymes which may be used to break down excess or worn-out cell parts. They may be used to destroy invading viruses and bacteria.

Question 16

What is the function of the Mitochondrion?

Answer 16

The mitochondrion is responsible for producing energy in the form of ATP. It does so through cell respiration.

Question 17

What is the function of the Chloroplast?

Answer 17

The chloroplast is responsible for photosynthesis, which converts light energy into chemical energy. It is only found in autotrophic organisms, which includes plant cells.

Question 18

What is the function of Vacuoles?

Answer 18

Vacuoles are similar to vesicles in that they are made up of phospholipid bilayers. Their role is to store water and can be quite large in plants, which provides structural support.

Question 19

What is the function of Cell Wall?

Answer 19

The cell wall is a rigid structure that is found outside the cell membrane in plant cells. Plant cell walls are composed of cellulose. Just like in prokaryotes, it provides structural support.

Question 20

What are the primary differences between animal and plant cells?

Answer 20

1. Plant cells contain chloroplasts.
2. Plant cells have large vacuoles, animal cells have small vacuoles.
3. Plant cells have cell walls.
4. It is common for animal cells to have lysosomes but they are uncommon in plant cells.