Unit 2 - Cells and Organelles

Question 1

Define Organelles

Answer 1

Membrane bound compartment within the cell each providing distinct environments and therefore conditions for different cellular reactions

Question 2

Function of a plant cell wall

Answer 2

• Found in plant cells, fungi cells and unicellular organisms
• Gives structure to the cell

Question 3

Function of the nucleus

Answer 3

• Contains chromosomal DNA
• Has its own double membrane
• Considered the control centre of a cell

Question 4

Function of a lysosome

Answer 4

• Small membrane-bound sacks that contain enzymes
• These enzymes break down fats, proteins and other unwanted materials inside the cell
• Can be seen with an electron microscope only

Question 5

Function of a Ribosome

Answer 5

• Smallest major organelle
• Found everywhere in the cell
• Location of protein synthesis
• Can be seen with an electron microscope only

Question 6

Function of (RER) Rough Endoplasmic Reticulum

Answer 6

A system of membranes enclosing a fluid filled space, the membrane surface is covered with ribosomes, folds and processes proteins made by the ribosomes packaging them into vesicles.

Question 7

Function of (SER) Smooth Endoplasmic Reticulum

Answer 7

A system of membranes enclosing a fluid-filled space, synthesises and processes lipids

Question 8

Function of a Vesicle

Answer 8

A small fluid filled sac in the cytoplasm surrounded by a membrane, transports substances in and out of the cell, via the cell surface membrane, and between organelles.

Question 9

Function of Golgi Apparatus

Answer 9

• Has a large surface area to volume ratio
• Receive, sort, store and secrete proteins
• Can be seen with an electron microscope only

Question 10

Function of mitochondria

Answer 10

• Has its own membrane and DNA
• Responsible for respiration
• Is considered the “powerhouse” of the cell

Question 11

Function of Chloroplast

Answer 11

• Has its own membrane and DNA
• Contains the chemical chlorophyll
• Responsible for photosynthesis
• Only found in plant cells

Question 12

Function of centriole

Answer 12

Component of the cytoskeleton present in most eukaryotic cells. Small hollow cylinders containing microtubules. Two associated centrioles form the centrosome, which is involved in the assembly and organisation of the spindle fibres, and therefore the splitting chromosomes during cell division.
Structure = sets of three microtubules with one in the center.

Question 13

Function of Cilia

Answer 13

Small hair-like structures found on the surface membrane of some animal cells. Microtubules allow the cilia to move which is used to move substances along the cell surface e.g. In the trachea to sweep dust and dirt out of the lungs.

Question 14

Function of Flagella

Answer 14

Long hair-like Structures that stick out from the cell surface and are surrounded by the plasma membrane. Microtubules contract to make flagellum move, this is used to propel cells forward e.g. the tail of a sperm cell, this requires energy.

Question 15

What are similarities between prokaryotic and eukaryotic cells?

Answer 15

They both have a cell membrane, cytoplasm and ribosomes

Question 16

Function of the Nucleolus

Answer 16

• Located within the nucleus
• Produced ribosomal RNA
• Important in protein synthesis

Question 17

Function of the Vacuole

Answer 17

• Stores water and soluble nutrients in cells
• Primarily found in plant cells

Question 18

Function of the Membrane

Answer 18

• Surrounds the cell and some other organelles
• Selectively permeable
• Allows substances into and out of the cell
• Can be seen with an electron microscope only