B1.1 Cell Structures Flashcards Preview

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Flashcards in B1.1 Cell Structures Deck (30)
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1
Q

Eukaryotic cell

A

Cells whose genetic material is contained within a nucleus

2
Q

Prokaryotic cell

A

Cells whose genetic material floats within the cytoplasms

3
Q

Name the organelles ALL eukaryotic cells contain.

A

Nucleus

Cell membrane

Mitochndria

Cytosplasm

4
Q

Name the EXTRA subcellular structures found in plants to animal cells.

A

Chloroplast

Cell Wall

Vacuole

5
Q

Function of the nucleus

A
  • Controlling the activities in the cell
  • Contains the organisms genetic material, arranged as chromosomes
  • Determines cells appearance and function
6
Q
  • The ‘power-house’ of the cell.
  • Provides energy by respiration
A

Mitochondria

7
Q

Function of the cell membrane

A
  • Delicate surface membrane made of two layers of phospholipid
  • Holds the cell together
  • Controls what goes in and out of the cell
8
Q
  • Transfers energy, makes things, and stores food.
  • Jelly-like substance where hundreds of reactions take place, which make up metabolism.
A

The cytoplasm

9
Q

This cell type is complex and relatively large 10-100 μm

A

Eukaryotic e.g. plant & animal cells

10
Q

Which English inventor and scientist where discovered cells using his self-designed microscope in 1665?

A

Robert Hooke

11
Q

MRS GREN

A

M = ovement

R = espiration

S = ensitivity

G = rowth

R = eproduction

E = xcretion

N = utrition

12
Q

This cell type is simple and typically smaller ~1-10 μm

A

Prokaryotic cells e.g bacteria cells

13
Q

What are ribosomes and what is their function?

A

Ribosomes are tiny granules on the membranes in the cytoplasm.

Ribosomes are where proteins are made in the cell.

14
Q

This organelle harnesses energy from the sun for photosynthesis

A

Chloroplast

15
Q

What is a a vacuole and what is its function?

A
  • Vacuole a large cavity filled with a watery fluid called cell sap.
  • It helps keep the cell rigid, pushing outwards.
16
Q
  • This structure surrounds the cell.
  • It is made of cellulose, a tough rubbery fibre.
  • It gives the cell rigidity and supports the cell.
A

Cell wall

17
Q

Name of primative bacteria-like organisms

A

Archaea

18
Q

What is a plasmid and how can it be advantageous?

A
  • A circular piece of DNA found in bacteria cells
  • Not needed for day-to-day survival but can give the bacterium advantages such as antibiotic resistance
19
Q

Tiny ‘hair-like’ structures that allow the cell to attach to structures, such a the cells in your digestive tract. They are also used to transfer genetic material between bacteria cells.

A

Pili

20
Q

What is the function of a slime capsule?

A
  • Protects bacteria from drying out and from poisonous substances.
  • Helps bacteria to stick to smooth surfaces
21
Q

List the structures and organelles you would expect to find in a bacteria cell.

A
  • Cell wall (peptigoglycan)
  • Cell membrane
  • Flagella
  • Single-loop DNA
  • Plasmids
  • Pili
  • Cytoplasm
  • Slime capsule
22
Q

State three examples of commonly found bacteria

A
  • Escherichia coli – Causes food poisoning
  • Streptococcus – bacteria causes sore throats
  • Streptomyces – bacteria found in soil and used to develop antibiotic streptomycin
23
Q

Tail-like structures that allow bacteria cells to move through liquids

A

Flagellum

24
Q

Name the parts of a light microscope

A
  • Body tube
  • Fine focussing knob
  • Mechanical stage
  • Stage
  • Objectives
  • Course focussing knob
  • Revolving nosepiece
  • Lens
  • Mirror
  • Arm
  • Base
25
Q

What is the equation for magnification?

A

Image size = Actual size x Total Magnification

26
Q

Resolution

A
  • The degree to which it is possible to distinguish between two objects that are very close together, rather than them look merged into one object.
  • The higher the resolution, the greater the detail you may see
27
Q

Name the two types of electron microscope

A
  • Transmission electron microscope (TEM)
  • Scanning electron microscope (SEM)
28
Q

What are TEM used for and how have they advanced science?

A
  • TEM is used to examine an extremely thin slice or section of cells or tissues
  • TEM has revealed subcellular structures in cells not visible with a light microscope such as mitochondria and chloroplasts
29
Q

What are SEM used for and how have they advanced science?

A
  • SEM has a large depth of field so can be used to examine the surface structure of specimens.
  • They produce a 3-D image of a surface by bouncing a beam of electrons off of a specimen.
30
Q

What are the advantages and disadvantages of light microscope and electron microscopes?

A

Light microscope

  • Cheep to buy and operate
  • Small and portable
  • Simple to prepare sample
  • Natural colour of sample is seen unless staining is used.
  • Specimens living or dead
  • Resolution up to 0.2 µm
  • (2 x 10-7 m)

Electron Microscope

  • Expensive to buy and operate
  • Large and difficult to move
  • Sample preparation is complex
  • Black and white images produced; false colour can be added to images
  • Specimens are dead
  • Resolution up to 0.1 nm
  • (1 x 10-10 m)