Cell Structure + Microscope

Question 1

What are the two prokaryotic domains?

Answer 1

Archaea and Eubacteria

Archaea are primitive bacteria that live in extreme conditions, while Eubacteria have a peptidoglycan cell wall.

Question 2

List the eukaryotic domains.

Answer 2

• Protista
• Fungi
• Plantae
• Animalia

These domains represent the major groups of eukaryotic organisms.

Question 3

What is the function of the nucleus?

Answer 3

Controls activities of the cell, carries out protein synthesis, and facilitates cell division

It contains nucleoplasm and large nuclear pores for substance movement.

Question 4

What organelle is the site of chemical reactions for aerobic respiration?

Answer 4

Mitochondria

Mitochondria release ATP and have a double membrane with inner folds called cristae.

Question 5

Describe the Golgi Apparatus.

Answer 5

A group of fluid-filled membrane-bound sacs that processes and packages lipids and proteins

It has a cis face for receiving proteins and a trans face for exporting vesicles.

Question 6

What are Golgi Vesicles?

Answer 6

Small fluid-filled sacs produced by the Golgi apparatus

They contain modified lipids and proteins for storage or transport.

Question 7

What is the function of lysosomes?

Answer 7

Digest invading cells and break down worn-out cellular components

Lysosomes are membrane-bound organelles that release digestive enzymes.

Question 8

What distinguishes prokaryotic ribosomes from eukaryotic ribosomes?

Answer 8

Prokaryotic ribosomes are 70s, while eukaryotic ribosomes are 80s

Ribosomes are the site of protein synthesis.

Question 9

What is the primary function of the Endoplasmic Reticulum?

Answer 9

Increase surface area for chemical reactions and transport materials

It consists of smooth (sER) and rough (rER) types, with rER involved in protein folding and sER in lipid synthesis.

Question 10

Different types of cell wall

Answer 10

• Cellulose (in plants)
• Chitin (in fungi)
• Peptidoglycan (in bacteria)

Animal cells do not have a cell wall.

Question 11

What is the function of chloroplasts?

Answer 11

Site of photosynthesis

They contain chlorophyll and have internal structures called grana and stroma.

Question 12

What do centrioles do?

Answer 12

Separate chromosomes during cell division

Centrioles are small hollow cylinders made of protein microtubules.

Question 13

What is the structure of cilia and flagella?

Answer 13

9+2 structure (9 protein microtubules in a ring with 2 in the middle)

They are involved in movement; cilia move substances along surfaces, while flagella propel cells.

Question 14

What is the function of the cytoskeleton?

Answer 14

Provides mechanical strength, shape, and aids in transport and cell division

Eukaryotic cytoskeleton consists of microfilaments and microtubules.

Question 15

Define differentiation.

Answer 15

Process that stem cells undergo to become specialized

This process allows cells to perform specific functions.

Question 16

What is magnification?

Answer 16

Making an image larger than the actual object

It is a measure of how many times larger an image is than the real object.

Question 17

What is resolution in microscopy?

Answer 17

Measure of how closely two separate points can be distinguished

Higher resolution allows for clearer images of structures.

Question 18

What is the maximum resolution of light microscopes?

Answer 18

0.2 micrometers

They are used for observing larger structures like cells and organelles.

Question 19

What is a disadvantage of electron microscopes?

Answer 19

Large, expensive, and cannot observe live specimens

They produce images in black and white and require a vacuum.

Question 20

What is the difference between Transmission Electron Microscopes (TEMs) and Scanning Electron Microscopes (SEMs)?

Answer 20

TEMs produce 2D images with higher resolution, while SEMs produce 3D images of surfaces

TEMs use electrons transmitted through specimens; SEMs use electrons bouncing off surfaces.

Question 21

What is the role of the eyepiece graticule in microscopy?

Answer 21

To calibrate at each magnification for measurements

It helps convert eyepiece units to micrometers.

Question 22

What are the key points for biological drawing?

Answer 22

• No shading or sketching
• Sharp pencil
• Give a title
• Include magnification or scale bar
• Use straight lines with a ruler

Drawings should not have crossed lines or arrow heads.

Question 23

Describe the process of protein synthesis involving the RER and Golgi apparatus.

Answer 23

Proteins are synthesized on ribosomes, enter rER lumen, are modified, packaged into transport vesicles, and moved to the Golgi body for further modification and packaging into secretory vesicles

Microtubules facilitate the transport of vesicles.

Question 24

The role of the Golgi body in the secretion of the proteins?

Answer 24

Modifies the protein
Packages the protein into vesicles

Question 25

Describe the role of the RER in protein secretion ?

Answer 25

The rough RER contains ribosomes Ribosome translate the messenger RNA/MRNA Rough ER packages proteins into vesicles

Question 26

Plasma cells make large numbers of antibodies.Explain the relationship between ribosomes,the rough ER and Golgi body in these cells.

Answer 26

Plasma cells contain more rough ER and Golgi bodies than other cells Ribosomes produce antibodies Golgi body modifies antibodies Golgi body packages modified antibodies into vesicles for exocytosis

Question 27

Light microscopes ?

Answer 27

• they use light to form an image •maximum resolution of 0.2 micrometeres •they are small and cheap and used to observe larger structures •can produce coloured images and can me used on Living specimen

Question 28

Electron microscopes ?

Answer 28

•uses electrons to form and image •maximum resolution of 0.0002 micrometeres •used to observe smaller structures •large and expensive and only produces images in black and white •specimen must be viewed in a vacuum so specimen cant be living

Question 29

Eukaryotic vs prokaryotic?

Answer 29

Eukaryotic 80s ribosomes , both membrane and non membrane bound organelles , cell wall cellulose (plant) or chintin (fungi) , dna associated with histones and are linear ** Prokaryotic 70s ribosomes,circular DNA, no membrane bound organelles and cell wall made of peptidoglycan .

Question 30

How to prepare a slide ?

Answer 30

1. Take a thin slice of your specimen and place it onto a clean microscope slide 2.add a drop of water or stain unto the specimen 3.take a clean cover slip and lower it slowly onto the specimens this avoids air bubbles