B1.1 Cell Structures

Question 1

<p>Eukaryotic cell</p>

Answer 1

<p>Cells whose genetic material is contained within a nucleus</p>

Question 2

<p>Prokaryotic cell</p>

Answer 2

<p>Cells whose genetic material floats within the cytoplasms</p>

Question 3

<p>Name the organelles ALL eukaryotic cells contain.</p>

Answer 3

<p>Nucleus</p>

<p>Cell membrane</p>

<p>Mitochndria</p>

<p>Cytosplasm</p>

Question 4

<p>Namethe EXTRA subcellular structures found in plants to animal cells.</p>

Answer 4

<p>Chloroplast</p>

<p>Cell Wall</p>

<p>Vacuole</p>

Question 5

<p>Function of the nucleus</p>

Answer 5

<ul> <li>Controlling the activities in the cell</li> <li>Contains the organisms genetic material, arranged as chromosomes</li> <li>Determines cells appearance and function</li></ul>

Question 6

<ul> <li>The 'power-house' of the cell.</li> <li>Provides energy by respiration</li></ul>

Answer 6

<p>Mitochondria</p>

Question 7

<p>Function of the cell membrane</p>

Answer 7

<ul> <li>Delicate surface membrane made of two layers of phospholipid</li> <li>Holds the cell together</li> <li>Controls what goes in and out of the cell</li></ul>

Question 8

<ul> <li>Transfers energy, makes things, and stores food.</li> <li>Jelly-like substance where hundreds of reactions take place, which make up metabolism.</li></ul>

Answer 8

<p>The cytoplasm</p>

Question 9

<p>This cell type is complex and relatively large 10-100 μm</p>

Answer 9

<p>Eukaryotic e.g. plant & animal cells</p>

Question 10

<p>WhichEnglish inventor and scientistwhere discovered cells using his self-designed microscope in 1665?</p>

Answer 10

<p>Robert Hooke</p>

Question 11

<p>MRS GREN</p>

Answer 11

<p>M = ovement</p>

<p>R = espiration</p>

<p>S = ensitivity</p>

<p></p>

<p>G = rowth</p>

<p>R = eproduction</p>

<p>E = xcretion</p>

<p>N = utrition</p>

Question 12

<p>This cell type is simple and typically smaller ~1-10 μm</p>

Answer 12

<p>Prokaryotic cells e.g bacteria cells</p>

Question 13

<p>What are ribosomes and what is their function?</p>

Answer 13

<p>Ribosomes are tiny granules on the membranes in the cytoplasm.</p>

<p>Ribosomes are where proteins are made in the cell.</p>

Question 14

<p>This organelle harnesses energy from the sun for photosynthesis</p>

Answer 14

<p>Chloroplast</p>

Question 15

<p>What is a a vacuole and what is its function?</p>

Answer 15

<ul> <li>Vacuole a large cavity filled with a watery fluid called cell sap.</li> <li>It helps keep the cell rigid, pushing outwards.</li></ul>

Question 16

<ul> <li>This structure surrounds the cell.</li> <li>It is made of cellulose, a tough rubbery fibre.</li> <li>It gives the cell rigidity and supports the cell.</li></ul>

Answer 16

<p>Cell wall</p>

Question 17

<p>Name of primative bacteria-like organisms</p>

Answer 17

<p>Archaea</p>

Question 18

<p>What is a plasmid and how can it be advantageous?</p>

Answer 18

<ul> <li>A circular piece of DNA found in bacteria cells</li> <li>Not needed for day-to-day survival but can give the bacterium advantages such as antibiotic resistance</li></ul>

Question 19

<p>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.</p>

Answer 19

<p>Pili</p>

Question 20

<p>What is the function of a slime capsule?</p>

Answer 20

<ul> <li>Protects bacteria from drying out and from poisonous substances.</li> <li>Helps bacteria to stick to smooth surfaces</li></ul>

Question 21

<p>List the structures and organelles you would expect to find in a bacteria cell.</p>

Answer 21

<ul> <li>Cell wall (peptigoglycan)</li> <li>Cell membrane</li> <li>Flagella</li> <li>Single-loop DNA</li> <li>Plasmids</li> <li>Pili</li> <li>Cytoplasm</li> <li>Slime capsule</li></ul>

Question 22

<p>State three examples of commonly found bacteria</p>

Answer 22

<ul> <li> <p>Escherichia coli – Causes food poisoning</p> </li> <li> <p>Streptococcus – bacteria causes sore throats</p> </li> <li> <p>Streptomyces – bacteria found in soil and used to develop antibiotic streptomycin</p> </li></ul>

Question 23

<p>Tail-like structures that allow bacteria cells to move through liquids</p>

Answer 23

<p>Flagellum</p>

Question 24

<p>Name the parts of a light microscope</p>

Answer 24

<ul> <li>Body tube</li> <li>Fine focussing knob</li> <li>Mechanical stage</li> <li>Stage</li> <li>Objectives</li> <li>Course focussing knob</li> <li>Revolving nosepiece</li> <li>Lens</li> <li>Mirror</li> <li>Arm</li> <li>Base</li></ul>

Question 25

<p>What is the equation for magnification?</p>

Answer 25

<p>Images size = Actual size / Magnification</p>

Question 26

<p>Resolution</p>

Answer 26

<ul> <li>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.</li> <li>The higher the resolution, the greater the detail you may see</li></ul>

Question 27

<p>Name the two types of electron microscope</p>

Answer 27

<ul> <li>Transmission electron microscope (TEM)</li> <li>Scanning electron microscope (SEM)</li></ul>

Question 28

<p>What are TEM used for and how have they advanced science?</p>

Answer 28

<ul> <li>TEM is used to examine an extremely thin slice or section of cells ortissues</li> <li> <p>TEM has revealed subcellular structures in cells not visible with a light microscope such as mitochondria and chloroplasts</p> </li></ul>

Question 29

<p>What are SEM used for and how have they advanced science?</p>

Answer 29

<ul> <li> <p>SEM has a largedepth of fieldso can be used to examine the surface structure of specimens.</p> </li> <li> <p>They produce a 3-D image of a surface by bouncing a beam of electrons off of a specimen.</p> </li></ul>

Question 30

<p>What are theadvantages and disadvantages of light microscope and electron microscopes?</p>

Answer 30

<p><u><strong>Light microscope</strong></u></p>

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

<p></p>

<p><u><strong>Electron Microscope</strong></u></p>

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