Bio lab mid term
two cellular components found in plant cells but not animal cells are
a cell wall and chloroplasts
in the energy profile below, which line represents the enzymatic reaction?
dotted red line (the lower one)
_________ reduces the amount of energy required to break bonds within macromolecules.
enzymes
eukaryotic cells differ from prokaryotic cells in a number of ways. which statement about these differences is not correct?
eukaryotic cells have a plasma membrane while prokaryotic do not
always start with the highest power objective when using the microscope
false
external structures that protrude from cells surface of some cells perform various function
flagellum
you find yourself working in a lab where they are testing for the success of a new vaccine on its ability to fight off the flu virus. in your experiment, you've injected the vaccine into lab rats, and looked at their ability to fight off the flu when it was introduced into their environment. What is the independent variable in this experiment?
flu vaccine
based on the information provided, what is the best way to proceed?
formulate a new hypothesis that the illness is cause by polished rice and proceed to test this hypothesis
stage
general location where specimen slide is placed and brought into focus using adjustments knobs that move vertically
You're outside for a walk at the Greenway on a crisp, spring morning, and you notice that there are different organisms collecting nectar from different colored flowers. You're curious if there is any preference in some organisms to a particular color of flower, so you design an experiment using ruby-throated hummingbirds and record how often they choose the nectar of different colored flowers. What would be the dependent variable for this experiment?
hector consumed
when an explanation for a phenomenon has been thoroughly tested and confirmed and generally accepted as true, in the scientific community this constitutes a
scientific theory
match the enzyme to the type of macromolecule that it digests
proteins-pepsin polysaccarides-amylase lipids-lipase
base and arm
provide support and stability for the microscope
The specific cell component where proteins are made/synthesized is _____,which are too small to be visible within the muscle cell under a microscope
ribosomes
objective lenses
second set of lenses each responsible for providing resolving power
mechanical stage
specific area for placing a slide which has clips that secure the slide onto the stage
Which solution would be best to test for the presence of oil/lipids?
sudan IV
condenser
system of lenses that focuses light onto the specimen
For the enzymatic digestion lab, you used test tube 1 containing pepsin, test tube 2 containing Hydrochloric acid, and test tube 3 containing artificial gastric juice. In which test tube did the digestion occur, and what color did the tube turn ?
test tube 3, pink
which part of the compound light microscope is used to adjust the amount of light striking the specimen being viewed?
the diaphragm
ocular lens
the part you look into to view a specimen
Which of the following is true of eukaryotes?
they are usually larger than prokaryotes, they contain a nucleus, they contain membrane bound organelles
based on the results of the experiment that was performed, what conclusion did the scientists draw, especially in relation to their hypothesis?
they concluded that the illness was not caused by a bacteria so their hypothesis was not supported ( was incorrect)
Which of the following is/are true of enzymes?
they require a specific pH and temperature and they lower the activation energy needed to cause a reaction
if you were observing a specimen using the oil-immersion objective, your total magnification would most likely be
1000x
the magnification for the ocular lens is
10x
low power objective lens
10x-20x
based on a daily intake of 2,000 calories, about how much total cholesterol is recommended as a daily total?
300 mg
When examining a section of skeletal muscle tissue under a compound light microscope, you want to increase the magnification in order to see the striations of the cells. You decide to increase the magnification by changing from the 10X objective lens to the 40X objective lens. By what magnitude is the true magnification increased by changing from the 10X to the 40X objective lens?
300x
what is the ideal temperature (during celsius) of pepsin?
37
high power objective
40x-50x
scanning objective lens
4x-5x
oil immersion objective lens
60x-100x
the recommended limit for total fat per day is _____ grams while only _____ grams of this total can be saturated fat
75.0 20.0
Diffusion
A passive process of transport in which a substance moves from an area of high concentration to an area of low concentration until the concentration is equal across the space.
In the enzymatic digestion lab, we learned that ________ is a protein found in egg whites that is broken down in our stomach by an enzyme called _______.
Albumin: Pepsin
Passive transport
The transportation of substances across a membrane that does not require using energy.
Which of the following BEST explains the molecular importance of enzymes in digestion?
Enzymes lower the activation energy, allowing macromolecules to be broken into monomers more efficiently.
Sarah is trying to look at a bacterial sample on a microscope slide. After turning on the microscope, she places a slide on the mechanical stage and secures it. She is using a low-power objective lens on the microscope. After adjusting the light control, she immediately notices that she can see what looks like a tail extending from one end of the bacterial cell, but it is too blurry for her to make any observations. What is the structure that Sarah wants to see and what is the first thing that she should adjust on the microscope to get a clearer picture?
Flagella; coarse adjustment knob
Concentration gradient
Occurs when the distribution of a particular substance in a physical space is not equal
Which of the following best explains the relationship between Penicillium, a mold, and Staphylococcus, a bacterium?
Penicillium is known to kill Staphylococcus by producing an antibiotic.
In the enzymatic digestion lab, we used the Biuret reagent to determine whether digestion of our protein solution had occurred. What conclusion can be formed for protein solution that turned purple when mixed with Biuret?
Purple color indicates the presence of protein, which means that digestion has not occurred.
While performing the reagent tests on water, the control group, you notice that the addition of Lugol's solution had an intense color change and the resulting solution was black. What is a possible explanation for this outcome?
The test tube used was not cleaned properly from a previous experiment
Osmosis
The diffusion of water through a semipermeable membrane moving water from an area with a high concentration of water to an area of low water concentration.
Selective permeability
The property of a cell (plasma) membrane in which some substances are allowed to move across the membrane (enter or leave) easily while others are not.
You are given an unknown slide to observe under the microscope. When you are observing the organelles present, you are able to see a cell wall and various membrane bound organelles. What can you conclude your organism might be?
a eukaryote, plant cell
using the 40x objective to view the cheek cells, what were you able to see?
a nucleus but not the other organelles
which of the following best describes the function of an enzyme?
a protein that lowers the activation energy of a reaction
the correct description of what you see is
a rotated and upside down e resembling a lowercase "a"
what is the ideal pH of pepsin?
acidic
based on the scenario regarding the mystery illness and what you have learned about the steps of the scientific method, which of these statements is correct?
after observing the mysterious illness, the most likely question the scientist asked was what the cause of the illness was
When transporting the microscope or carrying it across a room, you should hold it by the _________ and ___________.
arm and base
You are in the lab trying to look at a sample of cheek cells on a microscope slide. After turning on the microscope and adjusting the light control, you rotate the lowest-power objective lens into place. You notice what looks like a group of cells, but they are just off to the side of your view. First, you want to move the cells to the left so that you can see them. How would you do this?
by turning the knob on the mechanical stage
match the monomer to the corresponding macromolecule
carb-simple sugar protein-amino acid nucleotide- nucleic acid
Which statement correctly pairs a macromolecule with its monomer?
carbohydrates; monosaccharides
while many bacteria do not have a capsule, almost all have a _____ which provides an additional layer of protection for the bacterial cell and prevents dehydration
cell wall
found in plant cells but not animal cells, the ______ mainly provides protection and structural support
cell walls
the best description for how the cells are arranged on the slide you are viewing Is
cells are connected to one another, arranged in vertical (top to bottom) columns
the slide you are viewing at 40x is showing
cells that are mainly rectangular shaped with a large nucleus in the center
what is a long whiplike structure that helps with movement through a propeller motion
cilia
in the cross section of the leaf, chloroplast are
concentrated near the top, this would optimize the capturing of light for photosynthesis
scientists in a lab are testing the effectiveness of a potential new vaccine using human volunteers. A number of the participants are given the actual drug while others receive a placebo. In the scientific method, participants receiving a placebo make up whats known as the
control group
in the. scientific method, testing a hypothesis requires a set up that enables gathering of data to determine whether the hypothesis is supported or not. based on the beriberi scenario match the terms on the left with the correct statement
control group: chickens not injected with infected blood test group: chickens injected with patients blood independent variable: type of blood dependent variable: how chickens respond to injections
what is the name of the process that produces the fat you identified in the above question?
hydrogeneration
The probable answer to the scientific question that was proposed is known as the
hypothesis
suppose you were driving home and suddenly traffic on the interstate came to a standstill and you thought that this is caused by an accident. This thinking would be your
hypothesis
in the scientific method, a hypothesis is the untested answer to a question/problem whereas a prediction is the outcome or result one expects to find in order for the hypothesis to be correct. in this example, the hypothesis is ______ while. the prediction is _____.
hypothesis: the illness is caused by a bacteria. prediction: chickens injected with patients blood will become infected while those not injected will not be infected
Sally is dissolving alka seltzer for lab and notices it is taking an exceptionally long time to dissolve. What type of water is Sally likely dissolving her alka seltzer in?
ice water
when researchers conduct studies using the scientific method, they often manipulate one variable and assess whether another variable is affected by or responds to those changes. The variable manipulated is the
independent variable
which variable is manipulated by the scientists in an experiment?
independent variable
the bacterial capsule as "viewed" through the microscope on this slide can be described as
light colored oval shapes with a dark center
Which of the following organelles of Eukaryotic cells serves as a repository for old organelles and some wastes?
lysosomes
Which structure is a projection of the membrane that is involved in providing additional surface area for absorption or secretion of substances?
microvilli
short hair like projections that beat back and fourth to provide movement or to move mucus and debris
microvilli
amylase is an enzyme that breaks down starches In the intestine. What are the break down products?
monosaccharides
The scientific method has some general recognized steps/ procedures. sort the following steps in the correct order data collection and analysis hypothesis question conclusion prediction observation
observation question hypothesis prediction data collection and analysis conclusion
which objective lens made it possible to view individual capsules?
oil immersion 100x
You are given an unknown solution with instructions to determine the macromolecules present. The solution turned purple when Biuret's solution was added, orange when Benedict's solution was added and placed in a hot water bath, light brown when Lugol's solution was added, and light pink when Sudan IV was added. When a drop of the unknown solution was placed on a brown paper sack, it dried leaving no residue. Which of the following foods is most likely in the unknown solution?
peanut butter milkshake
in the intestine, secreted chemicals neutralize the acid in the chyme and create a slightly basic environment. what pH and temperature combination would result in the highest amylase activity?
ph-8.0 temp- 37 degrees celsius
which of the following is not a type of lipid molecule? steroid phospholipid triglyceride polysaccharide
polysaccaride
Multiple connected monosaccharides form _____________.
polysaccharides
what is defined as the expected outcome of an experiment or investigation?
prediction
A vegetarian diet is rich in carbohydrates because of the high plant content, but many warn against the lack of what macromolecule in a vegetarian diet due to the lack of animal product?
proteins
cells on the intestines of animals need to stay connected to ensure that the contents of the intestines do not leak out. cells stay connected by attaching to adjacent cells by way of proteins categorized as cellular junctions. Intestinal cells are connected by _______ which form a watertight seal between two adjacent animal cells, and by _____ which act like spot welds between adjacent cells
tight junctions desmosome
what is the function of chloroplasts?
to make food through photosynthesis
what is the main function of the nucleus?
to store and protect DNA
which type of fat are you advised to completely avoid?
trans fat
the compound light microscope has two kinds of stages. the movement for the main stage is usually _____ whereas the movement for the mechanical stage is usually ____
vertical horizontal
did the scientist in this scenario incorporate replication and how do you know?
yes, its started that a "group of chickens" was used which indicates that there was more than one chicken, therefore there was replication