Lab Final Flashcards
What are the actual diameter field of view sizes for each lens?
4x - 4.40mm
10x - 1.75mm
40x - 0.44mm
What is the formula for the acutal size of a cell/organism?
(Diameter of field of view of selected objective) / (# of times the cell/organism can fit across the field of view)
All living organisms are made of cells and all living cells share four basic structural features: ______?
Plasma membrane
Cytoplasm
DNA
Ribosomes
Prokaryotic cells lack a _____ nucleus, but have a central area that contains the DNA called the ____.
Membrane-bound, nucleoid
True or False: Prokaryotic organisms have organelles.
False
What is the glycocalyx?
The gelatinous outer covering of bacterial cells which traps water and protects the bacterium from desiccation
What is a thick glycocalyx called?
A capsule, which serves to prevent the bacteria from being destroyed by an animal’s immune system when ingested or inhaled, or help the bacteria to adhere to surfaces
True or False: eukaryotic organisms are only multicellular
False. Eukaryotic organisms range from unicellular to multicellular.
What are colonial organisms?
They are the half-way point between unicellular and multicellular, they may be composed of a group structurally and functionally similar cells adhere to each other and may communicate with each other.
Which of the two are bigger: eukaryotes or prokaryotes?
Eukaryotes
True or False: all eukaryotic organisms do not have a cell wall?
False. Some eukaryotic organisms do not have a cell wall (animal cells), whereas others do (plant cells)
How do you calculate the Relative Total Pollution Index (rTPI)?
Multiply the Population Index (PI) by the frequency
What does each Total Pollution Index (TPI) range indicate?
< 2: Low organic pollution
2 - 4: Probable organic pollution
4 - 5: High organic pollution
What are the two types of light microscopy?
Fluorescence microscopy and Confocal Laser Scanning
What is fluorescence microscopy?
Fluorescent dyes or antibody-dye complexes are used to label specific molecules or organelles within the cell. In this type of microscopy, the resulting fluorescence is viewed on a black background
What is confocal laser screening microscopy?
Where a laser light source is focused onto a very thin plane within either a naturally fluorescent specimen or one treated with commercial fluorescent dyes. This type of microscopy is used to examine specimens that are too thick to be examined with fluorescence microscopy.
What is electron microscopy?
Where the imaged produced by a beam of high velocity electrons instead of a beam of light. Are useful for examining very small objects, such as the internal structure of cells. These microscopes also have a greater resolving power than light microscopes
Resolution vs. Magnification
Resolution is the ability to detect/distinguish structures that are very close together; magnification is the ability to make small objects appear larger.
What are the two types of electron microscopes?
- Transmission Electron Microscopy (TEM)
- Scanning Electron Microscopy (SEM)
Describe TEM microscopy.
A beam of electrons is transmitted through an extremely thin section of a specimen. The TWM has the best resolution of the internal organization of cells and their organelles
Describe SEM microscopy.
A beam of electrons is scanned over the surface of a specimen resulting in a detailed three-dimensional image of the surface of a specimen.
Prokaryotic organisms include two major groups: ___?
Bacteria and archaea
Eukaryotic organisms include four major groups: ___?
Plants, animals, fungi, and protists.
What are three structures that are present in plant cells but not animal cells?
Cell wall, plastids (chloroplasts), and a large central vacuole
What are the three main types of plastids?
Chloroplasts, chromoplasts, and leucoplasts
The colour of chloroplasts is due to the predominance of green pigments called ___?
Chlorophyll
Chlorophylls are located on a set of membranes inside the chloroplast called ___?
Thylakoid membranes
Chromoplasts contain what kind of pigment?
Carotenoids, which are typically yellow, orange, red, or dark purple in colour.
True or False: chromoplasts are present in both animals and plants
False, chromoplasts are only present in plants
What is the main function of chromoplasts?
It helps attract animals for pollination, as well as speed dispersal
Why are leucoplasts often difficult to distinguish with light microscopy?
Due to their small size and lack of pigment
Describe plasmids.
Smaller pieces of circular DNA
What are cyanobacteria?
Photosynthetic bacteria that contain the pigment chlorophyll as well as a blue-green pigment called phycocyanin. While this bacteria may be unicellular, they commonly form filaments or colonies. They also have a thick gelatinous sheath exterior to their cell walls.
What is ATP?
Adenosine tri-phosphate, energy-rich molecules. It is the primary source of energy used for cellular processes.
Describe chlorophyll
Green pigment, responsible for the absorption of light to provide energy for photosynthesis.
Describe plasmodesmata
Cytoplasmic connections through which plant cells communicate. Numerous plasmodesmata run through perforations and connect adjacent cells
In a single starch grain, there is a layered appearance, these layers are called _____, usually each striation corresponds to a day of starch deposition.
Striations
Describe anthocyanins and how they differ from chromoplasts
Anthocyanins are a calss of blue, purple and red pigments that occur in the central vacuoles of some plant cells. They are water soluble. This pigment comes from the central vacuole, not from plasmids.
What are the two basic types of epidermal cells?
Non-specialized cells (irregularly shaped cells that fit together like jigsaw pieces
Guard cells (regulate the opening and closing of the stomata)
Describe the stomata
Small pores through which gas exchange occurs.
What type of cytoskeletal fiber is present in cilia and flagella?
Microtubules
Describe photosynthesis
The process which uses light energy to synthesize sugars from carbon dioxide and water, while releasing oxygen as a by-product. 6CO2 + 6H2O –> C6H12O6 + 6O2
What is the function of the oculars on the compound microscope?
The viewpoint of the microscope
What is the function of the objective lenses on the compound microscope?
The primary optical lenses for specimen visualization on a microscope. Objective lenses collect the light passing through the specimen and focus the light beam to form a magnified image.
What is the function of the coarse/fine focus adjustment knobs on the compound microscope?
Two adjustment knobs are used to focus the microscope.
Coarse: brings the specimen into approximate or near focus.
Fine: sharpen the focus quality of the image. When viewing with a high-power objective lens, carefully focus by only using the fine knob.
What is the function of the condenser adjustment knob on the compound microscope?
Condensers are lenses that are used to collect and focus light from the illuminator into the specimen.
What is the function of the iris diaphragm on the compound microscope?
Changes the intensity and size of the light projected through the slide.
What is the function of the iris diaphragm on the compound microscope?
What is a flagella used for?
Locomotion.
What is the cell wall’s function?
Found immediately outside the plasma membrane, provides support and protection.
What is the mitochondria’s function?
Carries out cellular respiration and supplies most of the cell’s ATP.
What is the nucleolus’ function?
Where ribosome subunit assembly occurs.
What is the central vacuole’s function?
In plant cells, it is responsible for the storage of water, enzymes, ions, proteins, supports plant cell through maintenance of turgor pressure.
What is the nucleus’ function?
Contains most of the cell’s genetic material, controls cell function, site of DNA synthesis and RNA transcription.
What is the cilia’s function?
Facilitates locomotion, or to sweep fluid over the surface of the cell.
What is the plasma membrane’s function?
Regulates passage of substances in/out of the cell, and is selectively permeable.
What is the microtubules’ function?
Structure and movement of cilia and flagella, cell organization, and shape.
What is the contractile vacuole’s function?
Osmoregulation in animal-like protists.
What is the rough ER’s function?
Initial synthesis and sorting of proteins for export.
What is the Golgi apparatus’ function?
Modify, store, and ship products of the endoplasmic reticulum.
What is the ribosome’s function?
Synthesizes proteins.
True or false: animal cells are usually smaller than plant cells.
True
Why is it necessary to stain your cheek epithelial cells?
The cheek cells, like most animal cells are colorless. Stain is used to increase contrast, which allows you to the cell and its components more clearly.
What is a solute?
A substance that is dissolved in a solvent
What is a solvent?
A liquid that has dissolved or can dissolve one or more solutes
What is a solution?
a solvent and its dissolved solutes
Plasma membranes are selectively permeable; they allow certain kinds of relatively small molecules to pass through them freely in both directions by _____ and _____.
Diffusion and osmosis
Diffusion and osmosis are both what kinds of transport?
Passive transport processes