semester review biology
Photosynthetic activity can be measured using chloroplasts suspended in a buffered solution containing DCPIP, a dye that can accept electrons from the electron transport chain of photosynthesis. Transfer of electrons to DCPIP decreases the relative absorbance of a specific wavelength of light (605 nm) by a solution that contains the dye. A buffered solution containing chloroplasts and DCPIP was divided equally among six identical samples. The samples were placed at various distances from a lamp, and then all samples were exposed to white light from the lamp for 60 minutes at room temperature. Sample 3 was wrapped in foil to prevent any light from reaching the solution. At 20-minute intervals, the photosynthetic activity in each sample was determined by measuring the relative absorbance of light at a wavelength of 605 nm. The results of the experiment are provided below. Which of the following descriptions of photosynthesis best explains the results of the experiment?
(A)Availability of electrons for transfer to DCPIP depends on light energy.
Photosynthetic activity can be measured using chloroplasts suspended in a buffered solution containing DCPIP, a dye that can accept electrons from the electron transport chain of photosynthesis. Transfer of electrons to DCPIP decreases the relative absorbance of a specific wavelength of light (605 nm) by a solution that contains the dye. A buffered solution containing chloroplasts and DCPIP was divided equally among six identical samples. The samples were placed at various distances from a lamp, and then all samples were exposed to white light from the lamp for 60 minutes at room temperature. Sample 3 was wrapped in foil to prevent any light from reaching the solution. At 20-minute intervals, the photosynthetic activity in each sample was determined by measuring the relative absorbance of light at a wavelength of 605 nm. The results of the experiment are provided below. Which of the following provides the best indication that light is required for the activation of electron transfer reactions in chloroplasts?
(B)Comparing the observed results for sample 2 and sample 3
Photosynthetic activity can be measured using chloroplasts suspended in a buffered solution containing DCPIP, a dye that can accept electrons from the electron transport chain of photosynthesis. Transfer of electrons to DCPIP decreases the relative absorbance of a specific wavelength of light (605 nm) by a solution that contains the dye. A buffered solution containing chloroplasts and DCPIP was divided equally among six identical samples. The samples were placed at various distances from a lamp, and then all samples were exposed to white light from the lamp for 60 minutes at room temperature. Sample 3 was wrapped in foil to prevent any light from reaching the solution. At 20-minute intervals, the photosynthetic activity in each sample was determined by measuring the relative absorbance of light at a wavelength of 605 nm. The results of the experiment are provided below. Which of the following can be reasonably concluded from the experimental results?
(D)Light from a lamp can substitute for sunlight in stimulating chloroplast processes.
what is produced overall per glucose molecule
6 NADH, 2 FADH2, and 2 ATP.
A frog jumped 80 times and each time the length of the jump was recorded. The mean length of the jumps was 38cm with a standard deviation of 10cm. What can be deduced from this information?
68% of the jumps were between 28 and 48 cm.
Cancer can result from a variety of different mutational events. Which of the following is LEAST likely to result in the initiation of a cancerous tumor?
A defect in a cell cycle checkpoint prevents a cell from entering S phase.
The figure above shows a model of a ligand precursor being cleaved to produce an active ligand that binds to a specific receptor. Which of the following is most likely to reduce the binding of the active ligand to its receptor?
A mutation in the receptor gene that causes a substitution of a charged amino acid for a nonpolar amino acid in the ligand binding site of the receptor
When do homologous chromosomes separate?
Anaphase 1
What is the relationship between osmolarity, ADH release, and urine production?
As tissue osmolarity rises, more ADH is released, causing less water to be excreted as urine
which nucleic acid is directly involved in transcription
DNA and RNA
Thrips are insects that feed on rose pollen. Scientists noted that the thrips population increased in the spring and decreased dramatically during the summer. The researchers hypothesized that food abundance was the limiting factor for the population. Which of the following types of data would be most useful for the scientists to collect at regular intervals on a designated test plot of rose.
Density of rose pollen produced (g/m^2)
Which of the following best describes an advantage that eukaryotic organisms have over prokaryotic organisms?
Eukaryotes have organelles that allow for compartmentalization of cellular processes, which increases the efficiency those process
Liver cells manufacture glycoproteins, while adipose cells store fat. Which of the following sub cellular structures is likely to be more prominent in liver cells than in adipose cells?
Golgi apparatus
What property of water makes it suitable as a coolant?
Has a high specific heat it can absorb a lot of heat
Which of the following questions is most relevant to understanding the calvin cycle?
How is ATP used in the formation of 3-carbon carbohydrates?
Enzymes with their highest activity at an alkaline (basic) pH are represented by which of the following graphs?
II only
If ATP breakdown (hydrolysis) is inhibited, which of the following types of movement across cell membranes is inhibited?
Passage of a solute against its concentration
what distinguishes rna from dna?
Rna-ribose; Dna- deoxyribose Rna-urical; Dna-thymine
Intravenous (IV) solutions administered to patients are normally isotonic. Which of the following is most likely if an IV of distilled water is administered to a patient?
The cells that are exposed to hypotonic solutions will expand as water moves osmotically into the cells from the blood
Researchers found E. coli that had mutation rates one hundred times higher than normal. Which of the following is the most likely cause of these results?
The proofreading mechanism of DNA polymerase was not working properly
Undersea landslides can disrupt marine habitats by burying organisms that live on the ocean floor. The graph above shows the size of a population of a certain organism that lives on the ocean floor. The population was affected by a recent landslide at the time indicated on the graph. Which of the following best predicts how the population will be affected by the landslide?
The reduced population will likely have allelic frequencies that are different from the initial population.
why-does-high-temperatures-cause-enzyme-to-lose-its-biological-probetries?
denatures it
in cell resperation what is the name of the proccess for glucoles breaking down into 2 pyruvates
glycolisis
Human skin shows continuous variation, what does this mean for human skin?
it is polygenic
Succinate dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction is inhibited by malonic acid, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Increasing the ratio of succinate to malonic acid reduces the inhibitory effect of malonic acid. What is malonic acid's role with respect to succinate dehydrogenase?
its a competitive inhibitor
What is the term used to discribe the failure of 2 sister chromitids?
nondisjunction
how is oxygen produced in photosynthesis
splitting of water
When a plant cell, such as one from a peony stem, is submerged in a very hypotonic solution, what is likely to occur?
the cell will become turgid
Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a 0.15 M salt solution become limp and soft. From this we can deduce that
the fresh water is hypotonic and the salt solution is hypertonic to the cells of the celery stalks.
the figure below illustrates a eukaryotic cell. Which of the following best describes how the three structures indicated by the arrows work together?
to synthesize and isolate proteins for secretion or for use in the cell
Which process occurs during the light-dependent reactions in photosynthesis?
water molecules are split
