B1.1 Cell Structures Flashcards
<p>Eukaryotic cell</p>
<p>Cells whose genetic material is contained within a nucleus</p>
<p>Prokaryotic cell</p>
<p>Cells whose genetic material floats within the cytoplasms</p>
<p>Name the organelles ALL eukaryotic cells contain.</p>
<p>Nucleus</p>
<p>Cell membrane</p>
<p>Mitochndria</p>
<p>Cytosplasm</p>
<p>Namethe EXTRA subcellular structures found in plants to animal cells.</p>
<p>Chloroplast</p>
<p>Cell Wall</p>
<p>Vacuole</p>
<p>Function of the nucleus</p>
<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>
<ul> <li>The 'power-house' of the cell.</li> <li>Provides energy by respiration</li></ul>
<p>Mitochondria</p>
<p>Function of the cell membrane</p>
<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>
<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>
<p>The cytoplasm</p>
<p>This cell type is complex and relatively large 10-100 μm</p>
<p>Eukaryotic e.g. plant & animal cells</p>
<p>WhichEnglish inventor and scientistwhere discovered cells using his self-designed microscope in 1665?</p>
<p>Robert Hooke</p>
<p>MRS GREN</p>
<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>
<p>This cell type is simple and typically smaller ~1-10 μm</p>
<p>Prokaryotic cells e.g bacteria cells</p>
<p>What are ribosomes and what is their function?</p>
<p>Ribosomes are tiny granules on the membranes in the cytoplasm.</p>
<p>Ribosomes are where proteins are made in the cell.</p>
<p>This organelle harnesses energy from the sun for photosynthesis</p>
<p>Chloroplast</p>
<p>What is a a vacuole and what is its function?</p>
<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>
<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>
<p>Cell wall</p>
<p>Name of primative bacteria-like organisms</p>
<p>Archaea</p>
<p>What is a plasmid and how can it be advantageous?</p>
<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>
<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>
<p>Pili</p>
<p>What is the function of a slime capsule?</p>
<ul> <li>Protects bacteria from drying out and from poisonous substances.</li> <li>Helps bacteria to stick to smooth surfaces</li></ul>
<p>List the structures and organelles you would expect to find in a bacteria cell.</p>
<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>
<p>State three examples of commonly found bacteria</p>
<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>
<p>Tail-like structures that allow bacteria cells to move through liquids</p>
<p>Flagellum</p>
<p>Name the parts of a light microscope</p>
<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>
What is the equation for magnification?
Images size = Actual size / Magnification
Resolution
- 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
Name the two types of electron microscope
- Transmission electron microscope (TEM)
- Scanning electron microscope (SEM)
What are TEM used for and how have they advanced science?
- 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
What are SEM used for and how have they advanced science?
-
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.
What are the advantages and disadvantages of light microscope and electron microscopes?
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)
