Bio Term 1 Test

Question 1

Difference between Light and Electron Micrograph (4)

Answer 1

• LM is coloured but EM is black and white
• LM shows a 2D image while EM shows a 3D image
• LM can zoom up 1000X but EM can zoom up to 200000X
• The ultrastructure of a cell can be seen through the EM but not the LM

Question 2

Organelles [Bacteria]

Answer 2

• Cell wall
• Cell membrane
• Ribosome
• Flagellum (pl. Flagella)
• DNA
• cytoplasm
• plasmid

Question 3

Organelles [virus]

Answer 3

• Protein coat
• Genetic material (DNA/RNA)

Question 4

About Bacterias

Answer 4

• single-celled organism
• No membrane bound nucleus
• Single circular DNA
• May have small circular DNA molecules known as plasmids
• Some bacteria are pathogenic (disease causing) while others are non-pathogenic (non disease causing)

Question 5

About virus

Answer 5

• A virus has both living and known living characteristics
• Does not have any cellular structure - cell membrane, cytoplasm, etc.
• It can reproduce, but only when it enters a living cell which acts as a host - host cell contains ribosomes, enzymes [necessary for reproduction]

Question 5

Cell wall [Functions]

Answer 5

gives the cell shape and structure and prevents the cell from injuring (Fully permeable) - made of cellulose

Question 5

Cytoplasm[Functions]

Answer 5

site where most cellular reactions occur

Question 6

NucleusFunctions]

Answer 6

controls all cellular activities and contains genetic materials such as DNA

Question 7

Chromatin[Functions]

Answer 7

composed mainly of DNA (chromatin threads condense to become chromosomes)

Question 8

RER[Functions]

Answer 8

1. Synthesises proteins (ribosomes are attached to the outer surface of the RER)
   
   1. The RER transports proteins made by ribosomes to the Golgi body fir secretion out of the cell

Question 9

Ribosomes[Functions]

Answer 9

1. Small round structures that are attached to the RER/lie freely in the cytoplasm
   
   1. Ribosomes attached to the RER → makes proteins that are usually transported out of the cell
   2. Ribosomes lying freely in the cytoplasm → Makes proteins that are used within the cytoplasm of the

Question 10

SER[Functions]

Answer 10

Synthesis of substances such as fats and steroids (Sex hormones), Converts harmful substances to harmless ones through detoxification

Question 10

Golgi apparatus[Functions]

Answer 10

Chemically modifies substances made by the ER, stores and packages these substances in vesicles to be discharged out of the cell

Vesicles fuse with GA and pinch out to carry proteins out of the cell

Question 10

Mitochondria[Functions]
abt the membraen aso

Answer 10

Site of aerobic respiration where energy is produced in the form of ATP (double membrane bound)

Question 11

Chloroplast[Functions]

Answer 11

Contains a green pigment called chlorophyll which is essential for photosynthesis (oval structures)

Question 11

Vacuoles[Functions]

Answer 11

1. A fluid-filled space enclosed by a partially permeable membrane, stores substances within a cell
   
   1. Plant Cell → large central vacuole which contains cell sap (dissolved sugar, mineral salts, amino acid)
   2. Animal Cell → many small vacuoles that contain water and food substances. (exists temporarily)

Question 12

Plasma Membrane[Functions]
**made of…

Answer 12

Partially permeable membrane that controls the movement of substances in and out of the cell (made of lipids and proteins)

Question 13

RER [Structure]

Answer 13

consists of a network of flattened spaces lined with a membrane

Question 13

Nucleus + chromosomes [Structure]

Answer 13

1. urrounded by a membrane called nuclear membrane
   
   1. Chromosomes - long thread-like structure found within the nucleus

Question 13

SER[Structure]

Answer 13

SER is more tubular than RER and is connected to the RER

Question 14

GA + Vesicles[Structure]

Answer 14

4. Shaped like a disc, consists of a stack of flattened spaces surrounded by a membrane
   
   1. Vesicles - tiny spherical spaces enclosed by a membrane

Question 15

Mitochondria[Structure]

Answer 15

Small, oval-shaped organelle

Question 15

Differentiation

Answer 15

process by which a cell becomes specialised for a
specific function

Question 15

Specialised cells

Answer 15

cells → tissues → organs → organ systems → organism

Question 15

Tissue

Answer 15

A group of cells that develop in the same way and have the same structure and functions

Question 16

What is the difference between free ribosomes and ribosomes attached to the RER

Answer 16

Free ribosomes are found in the cytoplasm and synthesise proteins for internal use, while ribosomes attached to the rough endoplasmic reticulum (RER) synthesise proteins for secretion or membrane incorporation.

Question 16

Organ

Answer 16

A group of tissues that have combined to form a single structure. The tissues work together to perform a specific overall function

Question 17

Organ System

Answer 17

A group of organs within and organism that function collectively to carry out a particular process

Question 18

How are the RER and GA related/Relationship between the RER and GA

Answer 18

After the rough endoplasmic reticulum (RER) synthesises proteins, it packages them into transport vesicles that travel to the Golgi apparatus (GA). In the Golgi apparatus, proteins undergo modification, sorting, and packaging into vesicles for transportation to their specific cellular destinations.

Question 19

Relationship between RER and mitochondrion

Answer 19

While the RER synthesises proteins, including those required for mitochondrial function, mitochondria, in turn, utilize these synthesised proteins to carry out aerobic respiration and produce ATP