2 - Basic Component of Living Systems

Question 1

What is the role of the rough endoplasmic reticulum?

Answer 1

(Ribosomes bound to outside)

Synthesis and transport of proteins

Question 2

What is the general structure of endoplasmic reticulum?

Answer 2

• network of membranes
• enclosing sacks called cisternae
• connected to the membrane of the nucleus

Question 3

What is the role of the smooth endoplasmic reticulum?

Answer 3

carbohydrate and lipid synthesis and storage

Question 4

Describe the structure of the mitochondria

Answer 4

• double membrane
• inside membrane folded into cristae
• filled with a fluid called a matrix
• cristae contain enzymes needed for aerobic respiration

Question 5

Describe the role and structure of vesicles

Answer 5

• membraneous sacks
• single membrane filled with fluid
• storage and transport roles

Question 6

-Where are lipids and carbohydrates synthesised?

Answer 6

smooth endoplasmic reticulum

Question 7

Where are proteins synthesised and transported from?

Answer 7

Rough endoplasmic reticulum

Question 8

Which organelle produces ribosmomes

Answer 8

Nucleus (in nucleolus)

Question 9

Define metabolism. Give 3 examples.

Answer 9

All the chemical reactions that take place within a cell

• respirations
• photosynthesis
• protein synthesis

Question 10

Define metabolite

Answer 10

A necessary or essential part of metabolism

Question 11

The nucleus is surrounded by what structure? Why?

Answer 11

Nuclear envelope

-protects from damage from the cytoplasm

Question 12

What is the structure fo the golgi appartus

Answer 12

• similar to SER
• compact
• formed of cisternae
• cis face (receiving vesicles)
• trans face (expelling vesicles)

Question 13

How is DNA transported in and out of the nucleus?

Answer 13

Transcribed into RNA so it is small enough to be exported through pores in the nuclear envelope

Question 14

What is the role of the mitochondria?

Answer 14

• final site of respiration

- energy from bonds in organic molecules converted to ATP

Question 15

Describe the structure of the nuclear envelope

Answer 15

• contains pores to allow molecules to move in and out

- surrounds the nucleus - protects it from damage

Question 16

Where are proteins synthesised?

Answer 16

Ribosomes

Question 17

How does an SEM microscope work?

Answer 17

Bounces electrons off the sample for a 3D image

Question 18

Define TEM

Answer 18

Transmission Electron Microscope

Question 19

Define SEM

Answer 19

Scanning Electron Microscope

Question 20

Give 2 advantages of a TEM microscope

Answer 20

• best mag (about 500,000x)

- best res (0.5nm)

Question 21

Give one advantage of an SEM microscope

Answer 21

produces a 3d image

Question 22

What is the function of the nucleus?

Answer 22

• contains coded genetic information

- directs the synthesis of proteins

Question 23

What are lysosomes and what are their roles?

Answer 23

• specialised forms of vesicles (membraneous sacs)
• Carry hydrolytic enzymes to catalyze hydrolysis reactions
• responsible for breaking down waste

Question 24

What is the structure of ribosomes? What are their roles

Answer 24

• found in the cytoplasm or attached to the RER
• made of RNA molcules
• NOT membrane bound

SITE OF PROTEIN SYNTHESIS

Question 25

How does a TEM microscope work?

Answer 25

Fires electrons through sample

Question 26

What is a dry mount and how is it prepared?

Answer 26

- solid whole specimens | - sectioned and placed on slide

Question 27

What is a wet mount?

Answer 27

Specimen suspended in oil or water

Question 28

What are 2 advantages of wet mounts?

Answer 28

- can be seen in motion | - more detail (oil)

Question 29

How do you prepare a smear slide adn what would you use it for?

Answer 29

- use edge of slide to spread a thin layer of specimen | - eg. blood

Question 30

How would you prepare a squash slide?

Answer 30

- wet mount prepared | - covered with slip and pressure applied from above

Question 31

What is differential staining useful?

Answer 31

Able to distinguish between 2 types of organism

Question 32

In microscopy, what is contrast?

Answer 32

The difference in shade between 2 objects

Question 33

What is resolution?

Answer 33

The smallest distance between two objects that can be seen as seperate

Question 34

Explain how diffraction limit resolution (5)

Answer 34

``` Diffraction happens when light passes through an object This causes rays to spread out Light rays overlap Objects not seen as separate Causes blurring ```

Question 35

Outline the basic concepts of cell theory

Answer 35

Cell is basic unit of life Both animal and plant tissue is made from cells Cells only develop from existing cells

Question 36

Describe the role of the two different lenses in compound microscopes and why they are present

Answer 36

Objective lens - magnifies sample Eye-piece lens - magnifies image from eye-piece lens Combined, this gives a large overlap magnification