CH.1 Cell Structure

Question 1

Magnification

Answer 1

The number of times larger an image of an object is than the real size of the object

Question 2

Resolution

Answer 2

the ability to distinguish between two objects very close together; the higher the resolution of an image, the greater the detail that can be seen

Question 3

state light microscope and electron microscope resolution and magnification

Answer 3

light microscope-
max. resolution: 200nm
magnification: 500x to 1500x.
electron microscope-
max. resolution: 0.5nm
magnification:2 million times

Question 4

Light microscope-
source of radiation
the wavelength of radiation used
lenses
specimen
stains
image

Answer 4

light waves
700nm-400nm
glass
live/non-living/dead
coloured dyes
coloured

Question 5

Electron microscope-
source of radiation
the wavelength of radiation used
lenses
specimen
stains
image

Answer 5

electrons
0.005nm
electromagnets
non-living or dead
heavy metals
black and white

Question 6

Cell Membrane (function and size)

Answer 6

7nm
The cell membrane is partially permeable and controls the exchange between the cell and its environment.

Question 7

Nucleus
Nuclear envelope
Nucleolus

Answer 7

The nucleus is the central control centre of the eukaryotic cell and is responsible for managing the cell’s genetic material.
A nuclear envelope is two membranes, situated close together, that surround the nucleus; the envelope is perforated with nuclear pores that control the exchange of materials between the nucleus and cytoplasm.
Nucleolus- function is to make ribosomes using information in its DNA.

Question 8

Ribosomes size

Answer 8

prokaryotic- 70S (20nm)
eukaryotic- 80S (25nm)

Question 9

Lysosomes (size)

Answer 9

0.1-0.5 micrometers

Question 10

Mitochondria (size)

Answer 10

1 micrometer

Question 11

Microtubules (size)

Answer 11

25nm diameter

Question 12

centriole (size)

Answer 12

500nm long

Question 13

Chloroplast (size)

Answer 13

diameter of 3-10 micrometers

Question 14

key structural features of a prokaryotic cell as found in a typical bacterium

Answer 14

• unicellular
• generally 1–5 µm diameter
• peptidoglycan cell walls
• circular DNA
• 70S ribosomes
• absence of organelles surrounded by double membranes

Question 15

organelles surrounded by a single membrane

Answer 15

lysosomes, Golgi apparatus, vacuoles, ER

Question 16

organelles surrounded by a double membrane

Answer 16

nucleus, mitochondrion, chloroplast

Question 17

organelles with no membrane

Answer 17

ribosomes, centrioles, microtubules

Question 18

structure of a typical virus
size

Answer 18

all viruses are non-cellular structures
a nucleic acid core (either DNA or RNA)
a capsid made of protein
some viruses have an outer envelope made of
phospholipids
20nm to 300nm