Biol Lab First Test
Methods Section Includes?
1. Preparation of your experiment 2. Data Collection Protocol (steps in scientific investigation)
Prokaryotes vs. Eukaryotes (7 differences)
1. Prokaryotes are usually unicellular while eukaryotes are usually multicellular. 2. Eukaryotes have nuclei that contain DNA. Prokaryotes have DNA but they are just found in cytoplasm. 3. Eukaryotes have membrane-bound organelles 4. Prokaryotes are much more abundant (10X the biomass) 5. Ribosomes 6. Projections...Flagella 7. Replication (binary vs asexual/sexual)
Eukarya Kingdoms
1. Protists 2. Animals 3. Plants (can have cell walls) 4. Fungi (can also have cell walls)
Three Domains of Microorganisms
Eukarya, Bacteria, Archeaa
Fungi Structure and Characteristics
Eukaryotic, heterotrophic, decomposing, multicellular
Spectrophotometer
Measures the amount of light absorbed and the amount of light transmitted as it passes through a solution. The more color there is in a solution, the more light it absorbs. Useful in measuring transmission over time. DPIP is able to absorb wavelength of light 605 nm best. And it is at this wavelength that change in DPIP transmittance over chloroplast transmittance is most easily recognizable.
Flagella
Much longer than Cilia. Use a whip-like motion to move. Usually only one or two. Beat in a wave-like manner for movement.
Animals
Multicellular, heterotrophs, Eukarya. Do ingestion, not absorption (Fungi do abosorption).
prokaryotic cells
evolved first, lacks a nucleus and membrane-bound organelles, has a general region called the nucleoid region which contains the DNA, contains ribosomes and various internal membranes, generally unicellular, some bacteria have cells walls and can use flagella for motility, cyanobacteria have chlorophyll a
B-Carotene
Yellow-Orange in color. Good dietary supplement.
Rate of Photosynthesis
%change in transmittance/time
Carotenoids Functions
1. Accessory pigments 2. Coloring of reproductive parts on flowers and fruits to enhance pollination
Gleocapsa Image and Structure
- Green - Gelatinous Sheath - ARE UNICELLULAR Cyanobacteria but still clustered
Oscillatoria Image and what it is?
- Oscillatoria- colonial blue green algea-- filament shape
Hypothesis requirements (2 things)
-if, then statements -testable
Three Shapes of Bacteria and their names
1. Bacilli- Rod 2. Cocci- Sphere 3. Spirilla- Spiral (corkscrew-shaped)
Elodea Organelles
1. Cell Wall 2. Chloroplasts 3. Nucleius 4. Vacuoles (can be filled with waste, enzymes, etc)
Euglena organelles
1. Chloroplast 2. ONE contractile vaculoe 3. Stigma - interior to the flagellum is this eye-spot which is light-sensitive structure that contains pigments known as carotenoids. 4. Nucleus 5. Pyrenoids- organelles that store sugars.
Two Types of Bacteria
1. Cyanobacteria (autotrophic... photosynthetic uses light as energy source.... chemosynthetic obtain energy from oxidation of inorganic substrance) 2. Bacteria- decomposers (return organic material to soil)
Explain "Photo" light-dependent reactions
1. Formation of ATP and NADPH for synthesis reactions 2. Splitting of water 3. Redox reactions of high-energy electrons thanks to light energy
Experiment Criteria (3 things)
1. Hypothesis leads to design of an experiment. 2. Purpose of experiment is to test hypothesis. 3. Experiments alter independent variables, keeping all other factors constant
Generate Testable Hypothesis (6 things)
1. Independent Variable- 1 clear cause 2. Dependent Variable- 1 clear effect 3. Eliminates all other variable except for the one being tested. 4. Avoid use of human feelings 5. Avoids use of purpose as an explanation of cause 6. If...then format
Steps of Scientific Method
1. List the steps in the scientific method as used in Biology 101. - Make observations- detect a problem and form a question - Form testable hypothesis (falsifiable) - Design repeatable experiments that test hypothesis
Methods of Soap Experiment
1. Three Agar Plates 2. Two plates cut in half with control and experimental on either half 3. On experimental halves, cleansed hands (different soaps for either one) are applied 4. On control halves, dirty hands are applied 5. On third plate, it is left in air (control experiment) 6. let it sit for week 7. Recorded bacteria growth results
Prokaryotes (details)
1. Unicellular 2. No Nucleus 3. No Membrane Bound Organelles 4. Simple DNA 5. Most abundant 6. Reproduce via Binary Fission 7. 2 domain groups studied in lab: bacteria and cyanobacteria
Resources needed for Photosynthesis
1. Water, CO2, Chloroplasts, light
DPIP reaction + What happens to DPIP
2DPIP+ Chloroplast+ H20 --> 2DIPIH2 + O2 As DPIP accepts electrons,
ch.3 objectives pre-lab
3 differences b/t prokaryotes and eukaryotes the difference b/t plant and animal cells and relate the differences in structure to their function forces that drive osmosis and diffusion correct microscope use including stage, scope, and objectives
ch.3 post-lab objectives
3 types of cellular motility characteristics of plant, animal, and protistan cells cell organelles and their function advantages of cellularity and multicellularity identify particular cells as seen in this lab\ use microscope to focus on an organism
What are contractile vacuoles and where are they found.
A Paramecium has a pair of these vacuoles, which remove excess water (remember that Paracecium live in fresh water environments) from the inside of the organism.
Yeast Image and what is it?
A fungi called Saccharomyces. Usually , one-celled and ferments glucose to ethyl alcohol in anaerobic condition. In the presence of oxygen, yeast is important in oxidizing glucose to CO2 (forms gas bubbles in rising bread dough), forms very large colonies over 4 mm wide, strikingly white and glistening. Furthermore, it is studied by taking toothpick in yogurt and placing sample of slide. Also, think wine, beer, and baking.
Paramecium Phylum and Kingdom (level of organization just below the kingdom)?
A paramecium is a PROTIST. Ciliophora-->> Paramecium is often referred to as Protozoans. Ciliophora has largest single-celled organisms and the most complex protozoans.
Scientific Method
A way of gathering and testing information used by many people, but especially in science.
Human Epithelial Cells
Abundant, prominent nuclei, bunched together. Some are specialized to allow materials to pass between cells or through cells to other side of protective layer. Have a protective layer which limit extra-cellular materials to move between cells.
Cyanobacteria
All blue-green algae are photosynthetic. The blue-green color suggests that they have chlorophyll-a. Cyanobacteria are also capable of nitrogen fixation. THEY DIFFER FROM OTHER PHOTOSYNTHETIC PROKARYOTES IN CHLOROPHYLL POSSESSION.
Micronucleus and Macronucleus
All ciliates (paramecium is a ciliates) have two types of nuclei. One macronucleus that is responsible for cell maintenance functions. Micornucleus (can be numerous) is responsible for genetic and reproductive functions, including producing a macronucles. Reproduction of ciliates can be asexual or sexual.
Control Group
All experiments should have a control, in which all the factors are kept the same as those of the test group except the one being tested, which is kept in its unmanipulated state.
Two Domains of Prokarya
Archaea, Bacteria
How do Euglena reproduce?
Asexual
Why is spectrophotometer set to 605 nm?
At this wavelength, changes in transmittance by DPIP against a background of transmittance by chlorophyll are most easily seen. One should the choose the wavelength at which the difference between the transmittance is the greatest.
Diseases in humans caused by?
Bacteria
Nitrogen Fixation
Bacteria do nitrogen fixation, which means they convert nitrogen from atmosphere into forms that can be used by plants.
Cyanobacteria
Blue Green photosynthetic algae. Unique to its kind, it has chlrophyll a and use water to produce oxygen gas as a byproduct. - Occurs in Unicellular or Colonial forms
Staphylococcus
Bunches of cocci. 2-3 mm wide, kind of opaque (kind of yellow). Common in skin. - Bacteria
End product of Photosynthesis
Carbs and oxygen power cell respiration.
What should each of the 4 tubes contain?
Calibration- 4 ml water, 1 ml buffer, 3 drops of chloroplast Boiled- 3ml of water, 1ml of buffer, 1 ml of DPIP, 3 drops of boiled chloroplast Unboiled- 3ml of water, 1 ml of buffer, 1ml of DPIP, 3 drops of unboiled chloroplast Dark- 3ml of water, 1ml of buffer, 1 ml of DPIP, 3 drops of unboiled chloroplast
Two Classes of Photoreceptors
Chlorophylls and Carotenoids
Cytoplasmic Streaming
Chloroplast in cytoplasm move throughout cell via cytoplasmic streaming.
Order of pigments on Chromatography paper/Chromatogram (complete array of colored bands) in order from origin to solvent front
Chlrophyll b, chlrophyll a, two Xanthophylls, and B-Carotene
Cell Motility Methods
Cilia, Flagella, or cytoplasmic streaming
Carotenoids Color
Color: Yellow, Orange, or Red pigments.
Chlorophyll-B Molecule
Color= Olive Green. This is an accessory pigment. They simply capture additional light that chlorophyll didn't. The light they absorb is transferred to Chlorophyll a.
Elodea Kingdom
Common pond weed found in NC. It is a PLANT for Christ Sakes.
Steps of Agar experiment?
Consult book.
Volvox colonies
Contain 500 to 50,000 cells. Lots of specialization to support such a large colony.
What happens to DPIP as it accepts electrons?
DPIP is a blue dye. When it begins to accept electrons, it will become colorless. We monitor this loss of color (and change in transmittance) with a spectrophotmeter.
Endosymbiont Theory
Describes how eukaryotic cells came to be. Implies that chloroplasts and mitochondria were once prokaryotes that lived on their own. One day, they were ingested by a larger prokaryote and the two formed a mutual symbiotic relationship. These two organelles provide energy for Eukarya.
Objective Vs. Subjective Observations
Distinguish between subjective and objective observations: Objective Observations: ones that can be verified-repeated and consistently interpreted by different observers. Often involve measuring or counting. Subjective Observations: are those that are observer-specific and may not be interpreted in the same way by different people. "Tree is tall or light green."
Goals of Experiment
Either support or disprove hypothesis
Euglena Feeding
Euglena can be either autotrophic (photosynthesis) or they can straight up be heterotrophic (feed by phagocytosis which is ingestion).
Euglena Rigidity
Euglena does not have a cell wall! It retains its rigidity with the help of elastic proteins which make up a layer called the pellicle.
Euglena Motility
Euglena move in a whip-like manner with the help of one functional flagellum.
Coliforms
Foul smelling. Can ferment lactose. Gram negative.
Chlorophyll-A Molecule
Found in Eukarya and Cyanobacteria. The essential light absorbing pigment. Color= Blue-Green.
Streptococcus
Found in chains. 1 mm wide, transparent. Very common in nose and mouth. Bacteria
Nucleoid Region
General region where prokaryote houses DNA.
Molds
Hairy fungi. Has Hyphae
How does a Paramecium move?
Has cilia! The rapid movement of cilia
Hypotheses (proven?)
Hypothesis can be disproved but NOT proved.
Conjugation
In conjugation, two cells exchange micronuclei and genetic material. In conjugation, each cell acts a "donor" and "recipient." Parameciums conjugate.
Evidence for Endosymbiont Theory
Mitochondria, chloroplasts have their own DNA and cellular processes.
Explain Oral Groove
Oral Grooves are found in paramecium. The rapid movement of a paramecium's cilia creates a groove on its side. Food particles accumulate at the lower end of the oral groove (this region is called the cytopharynx). A food vacuole envelops these food particles. Lysosomes then digest the material of the food vacuole that can be digested. The rest is shipped out of the cell as the vacuole goes to an opening called the anal pore and dumps contents while fusing with the membrane.
Photosynthetic Bacteria differences from photosynthetic eukarya?
Photosynthetic bacteria use light energy. However, they do not have chloroplasts, nor do they use electrons from water.
Plasmolysis
Plants shrink when placed in hypertonic solutions.
Bacillus
Rod-like shape. Over 3 mm wide. Bacteria (some decomposers)
Euglena
STILL A PROTIST. Has both animal and plant characteristics. - Usually unicellular, not considered ancestors of any other heterotrophic or autotrophic organism. Belongs to the Euglenophyta Division (plant equivalent of Phylum), which has most of its organisms in freshwater places.
Pseudomonas
Shoots out pigments
Robert Hill
Showed that chlorplast in water could release O2 with the hel of light and an electron acceptre--->>> showed that O2 comes from water, not CO2. -Also showed that the redox reactions initiated by light were essential to photosynthesis.
How to study bacteria? (Hint: What is Agar)
Smear bacteria samples on Petri plates filled with agar-based media. Agar is a polysaccharide in cell wall of some red-algea that help mediate the growth of bacteria. Agar-based medium- helps medium stay in place so bacteria can grow.
3 Xanthophylls
So similar it is hard to distinguish. All yellow pigments.
Importance of Light
Solar energy is the basis for life on Earth. It is trapped by photosynthesis (which is the conversion of light energy to chemical energy).
Pseudopodia
Some cells use pseudopodia (or false feet... still microtubules) for movement. These false feet extend from the body and pull the rest of the cell along with it. They act to anchor and pull cell structures during movement. EXAMPLE: Amoeba
Cilia
Some organisms have this tiny hair-like structure (made of microtubules) on their surface. Cilia use a whip-like motion in rows. They are also used in ingestion (think oral groove), cleaning of respiratory tract, and female eggs to help propel sperm.
Robert Koch
Started using Agar. Famous microbiologist. He learned of it from Frau Lina Hesse, who used the substance to keep her jellies solid in warm weather. Agar keeps the jell in petri dishes solid.
Protocal
Steps in a scientific investigation
Where does synthesis take place
Stroma
What do all Subjective Observations need to be qualified as scientific observations?
Subjective observations must be transformed into more objective observations. They need measured values to be supported.
Gelatinous Sheath
Surrounds unicellular cyanobacteria or gleocapsa.
Where are the chlorophyll-a molecules in the Cyanobacteria?
The chlorophyll is on the membrane, not in it.
Volvox Motility
The outer cells of Volvox community are bi-flagellate and coordinated beating of flagellum is what allows volvox colonies to move.
Photoreceptors
The pigments that trap light energy. They have varying solubilities and absorbency power.
Calibration Tube Purpose
The transmission on the Calibration Tube should be set to 100%. It calibrates the spectrophotmeter---> similar to balancing scale.
Chlorophylls
There are like 5 types of chlorophyll molecules that we know about. They all have same basic structure but just differ in the wavelengths of light they absorb (and thus differ in color).
Plants
These are multicellular eukarya. They have cellulose (make up their cell wall). They have unique double membrane organelle called plastids that perform various functions. Most plants are autotrophic and contain chloroplasts.
HILL Reaction Protocol and tube contents
These experiments will allow us to study light's affect on photosynthesis. We use 4 tubes. There are two controls (1 dark and 1 boiled chloroplast).
How to Paramecium eat?
They are heterotrophic. They eat by ingestion.
R(f) Value
This is an importance means of describing and distinguishing between different pigments. It is the distance of compound moves during chromatography in relation to the solvent front. Rf= (distance substance travels from origin)/(distance solvent travels from the origin) *Rf value reflects the affinity a substance has for the solvent front. Different color bands are seen because each substance has a different polarity. Polar molecules combine with the charged chromatopgrapy paper and do not move very far. Nonpolar substance travel with the solvent and do not stick to chromatography paper as much. *always a fraction between .01 and .99
Where does the light reaction take place?
Thylakoid Membrane
Why is Control used in Agar experiment?
To assure that the bacteria in the experiment is coming from the sample environment.
Purpose of deveining leaves?
To limit random parts of plant that will affect transmittance.
How to detect light reactions?
Use a dye (DPIP) that intercepts the flow of electrons and, thus, photosynthetic activities. DPIP takes the place of NADP+ and becomes reduced to DPIPH2.
Paper Chromatography
Used to analyze pigments (separated based on solubility in relation to solvent).
Microscopy
Using Light Microscopes to view Bacterium and other microorganisms
Protists
Usually unicellular, don't belong in any other kingdom, thus really artificial
Volvox Kingdom
Volvox belongs to Plant Kingdom and Chlorophyta Division (most complex representation of green algae).
What keeps Volvoc colony together?
Volvox cells are connected to one another by cytoplasmic strands. The entire colony, itself, is surrounded by a thin mucilaginous layer.
Daughter Colonies of the Volvox
Volvox colony makes it so that 50 cells are specialized for reproduction--> daughter colony within larger colony.
How do Paramecium move?
When a paramecium encounter an immovable object, it reverses direction. How? A change in electrical charge (because of the influx of calcium ions) triggers cilia to reverse its beating.
Carotenoid Sub-Groups
Xanthophylls and Carotenes.
Photosyntheis Formula
YOU KNOW IT.
molds
hairy-looking colonies, stains show hyphae (broken ends and size that distinguish them from bacilli)