Cell Structure

Question 1

What are Eukaryotes?

Answer 1

Eukaryotes are organisms made up of a cell or cells containing a membrane-bound nucleus

Question 2

What structures are found in all Eukaryotes?

Answer 2

• Cell membrane
• Cytoplasm
• Mitochondria
• Nucleus (except in red blood cells)

Question 3

What additional structures do plants have?

Answer 3

• Cell wall
• Chloroplasts
• Sap vacuole

Question 4

What is the structure and function of a cell membrane?

Answer 4

STRUCTURE:
-Made of phospholipids/ proteins

FUNCTION:

• Controls the passage of substances into and out of the cell
• Allows water and oxygen and nutrients to enter and waste like carbon dioxide to exit.

Question 5

What is the structure and function of chromosomal DNA?

Answer 5

STRUCTURE:
-One or more linear pieces of double-stranded DNA

FUNCTION:
-Stores genetic material required for the various cell processes

Question 6

What is the structure and function of cytoplasm?

Answer 6

STRUCTURE:

• Salt ions and sugars dissolved in it
• Fat molecules/ proteins suspended in it
• Contains food reserves and organelles

FUNCTION:

• Site of chemical reaction and contains enzymes that control these reactions
• Holds cell organelles

Question 7

What is the structure and function of the nucleus?

Answer 7

STRUCTURE:

• Largest organelle
• Surrounded by double membrane
• Contains DNA in the form of chromosomes (protein-bound DNA)

FUNCTION:
-Regulation of cell functions through directing the production of RNA and protein

Question 8

What is the structure and function of mitochondria?

Answer 8

STRUCTURE:
-Small organelle with an inner membrane (Cristae) and an outer membrane, and centered Matrix

FUNCTION:
-Controls the production and release of ATP from aerobic respiration

Question 9

What is the structure and function of a cell wall?

Answer 9

STRUCTURE:
-Made of cellulose fibers
-(algal cell wall) made of glycoprotein/ polysaccharides
 (fungal cell wall) made of chitin
 (bacterial cell wall) made of murein

FUNCTION:

• Provides mechanical strength
• Resists bursting when it takes in water by Osmosis

Question 10

What is the structure and function of chloroplast?

Answer 10

STRUCTURE:

• Surrounded by a double membrane
• Contain chlorophyll/ other pigments

FUNCTION:
-Absorbs light energy and converts it to chemical energy by the process of photosynthesis

Question 11

What is the structure and function of a vacuole?

Answer 11

STRUCTURE:
-A space surrounded by a membrane called the tonoplast containing cell sap (sugars/ salts)

FUNCTION:

• Stores water soluble chemical and ions
• Keeps cells turgid

Question 12

What Prokaryotes?

Answer 12

Single celled organisms- Bacteria

Question 13

How do Eukaryotes and Prokaryotes differ?

Answer 13

• Prokaryotic cells are much smaller than Eukaryotic cells
• Prokaryotes do not contain a nucleus
• Prokaryotes have a single circular DNA molecule that is not bound to proteins
• Prokaryotes have no membrane-bound organelles
• Ribosomes in Prokaryotic cells are much smaller than those in Eukaryotic cells
• Prokaryotes have plasmids (small, circular pieces of DNA), Eukaryotes do not
• Prokaryotes have a flagella that enables the cell to move, Eukaryotes do not
• Prokaryotes have a slime capsule that contains toxins for protection, Eukaryotes do not.

Question 14

What is a tissue?

Answer 14

A group of cells with a similar structure- acting together to perform a specific function

Question 15

What is an organ? Give 3 examples of different organs

Answer 15

A structure made up of a group of tissues working together to perform a shared function.
E.g, Heart, stomach and kidney

Question 16

What is an organ system? Give 3 examples

Answer 16

A group of organs with related functions working together to perform a body function.
E.g, Circulatory, Digestive and Excretory

Question 17

What is an organism?

Answer 17

A whole living being capable of reproduction