Bio final pt 4 (photosynthesis)

Students investigated the effect of light on the carbon cycle in aquatic ecosystems by performing a controlled experiment summarized below. The students placed equal amount of water (pH 7.0) from a large aquarium in glass beakers. The students transferred aquatic plants from the aquarium to several of the beakers, and then they placed equal numbers of the beakers in the light or the dark (Figure 1: groups 1 and II). Similarly the students transferred goldfish from the same aquarium to other beakers, and then they placed equal numbers of those beakers in the light or dark (Figure 1: groups and IV). Finally the students placed an equal number of beakers containing water only in the light or dark (Figure 1: groups V and VI). After exposing the samples to light or dark for several hours, the students recorded the pH of the water in each beaker. Carbon dioxide dissolves in water will lower the pH of an aqueous solution. In the experiment, the students used change in pH to monitor change in the amount of carbon dioxide in the water. For each treatment group, the students calculated the mean pH and standard error, as documented in the table below. Which of the following observations provides the best evidence that photosynthesis occurred in treatment group I?

C)The mean pH of the samples increased after one hour

Students investigated the effect of light on the carbon cycle in aquatic ecosystems by performing a controlled experiment summarized below. The students placed equal amount of water (pH 7.0) from a large aquarium in glass beakers. The students transferred aquatic plants from the aquarium to several of the beakers, and then they placed equal numbers of the beakers in the light or the dark (Figure 1: groups 1 and ). Similarly the students transferred goldfish from the same aquarium to other beakers, and then they placed equal numbers of those beakers in the light or dark (Figure 1: groups and IV). Finally the students placed an equal number of beakers containing water only in the light or dark (Figure 1: groups V and VI). After exposing the samples to light or dark for several hours, the students recorded the pH of the water in each beaker. Carbon dioxide dissolves in water will lower the pH of an aqueous solution. In the experiment, the students used change in pH to monitor change in the amount of carbon dioxide in the water. For each treatment group, the students calculated the mean pH and standard error, as documented in the table below. The results for treatment groups V and VI could suggest which of the following questions about the design experiment?

Does the aquarium water contain living microorganisms?

The most probably cause for the difference in mean stem length between plants in dish A and plants in dish B is which of the following?

Elongation of seedlings in response to the lack of light

Students investigated the effect of light on the carbon cycle in aquatic ecosystems by performing a controlled experiment summarized below. The students placed equal amount of water (pH 7.0) from a large aquarium in glass beakers. The students transferred aquatic plants from the aquarium to several of the beakers, and then they placed equal numbers of the beakers in the light or the dark (Figure 1: groups 1 and II). Similarly the students transferred goldfish from the same aquarium to other beakers, and then they placed equal numbers of those beakers in the light or dark (Figure 1: groups and IV). Finally the students placed an equal number of beakers containing water only in the light or dark (Figure 1: groups V and VI). After exposing the samples to light or dark for several hours, the students recorded the pH of the water in each beaker. Carbon dioxide dissolves in water will lower the pH of an aqueous solution. In the experiment, the students used change in pH to monitor change in the amount of carbon dioxide in the water. For each treatment group, the students calculated the mean pH and standard error, as documented in the table below. To investigate whether an organism in the study is capable of both photosynthesis and respiration, a comparison of which treatment groups is most appropriate?

I and IV

which of the following modifications to the experimental design will best help reduce the standard errors of the means?

Increasing the sample size of each treatment group

A student placed 20 tobacco seeds of the same species on moist paper towels in each of two petri dishes. Dish A was wrapped completely in an opaque cover to exclude all light. Dish B was not wrapped. The dishes were placed equidistant from a light source set to a cycle of 14 hours of light and 10 hours of dark. All other conditions were the same for both dishes. The dishes were examined after 7 days, and the opaque cover was permanently removed from dish A. Both dishes were returned to the light and examined again at 14 days. The following data were obtained. Additional observations were made on day 21, and no yellow-leaved seedlings were found alive in either dish. This is most likely because

Yellow-leaved seedlings were unable to convert given light energy into chemical energy

which of the following an difference between light dependent and light independent actions photosynthesis?

b) The light dependent reactions produce ATP and NADPH, the light independent use energy stored in ATP and NADPH

Which of the following questions is most relevant to understanding the Calvin Cycle?

b)How is ATP used in the formation of G3P?

Which of the following organisms is most likely to utilize only cyclic flow during the light reactions?

b)Purple Sulfur Bacteria

What is the relationship between the wavelength of light and the quantity of energy per photon?

b)They are inversely related.

18. Which of the reasons does not support the claim that photoautotrophs are all related?

c)All photoautotrophs use both cyclic and linear flow during light reactions

Where do light independent reactions occur?

c)B

The alternative pathways of photosynthesis using the C4 and CAM systems are compromises. Why?

c)Both minimizes photorespiration but expend more ATP

How is photosynthesis similar tin C4 plants and CAM plants?

c)In both cases, an intermediate 4-carbon molecule

Most of the water taken up by a plant is

c)Lost during transpiration

In chloroplasts ATP is synthesized from ADP plus inorganic phosphate (Pi) in a reaction catalyzed by ATP synthase molecules that are embedded in the thylakoid membrane . Which of the following statements provides the best evidence to support the claim that no ATP will be synthesized in the absence of a proton gradient across the thylakoid membrane?

c)No ATP is synthesized when channel proteins that allow the free passage of protons to be inserted into the thylakoid membrane

Carotenoids are often found in foods that are considered to have antioxidant properties in human nutrition. What related function do they have in plants?

c)They shield the sensitive chromosomes of the plant from harmful UV radiation.

The accumulation of free oxygen in Earth's atmosphere began

c)With the origin of cyanobacteria that had both photosystem I and II

The enzyme Rubisco is considered to be highly conserved because it is found in

d)All known photoautotrophs, both bacterial and eukaryotic

A researcher claims that increased atmospheric carbon dioxide levels cause increased growth rates in plants.Which of the following statements best supports the researcher's claim?

d)Atmospheric carbon dioxide is the raw material for photosynthesis, which plants rely or producing sugars

Where do the light dependent reactions occur?

d)C and D

Which of the following would tend to increase transpiration?

d)Higher Stomatal Density

In addition to the pigments commonly associated with photosynthesis, a certain photosynthetic 8p iss contains two additional pigments. Which of the following best supports the claim that this species is better adapted to environmental changes than other photosynthetic species?

d)The additional pigments allow the species containing then to harvest energy from wavelenging of light that other photosynthetic species cannot use.

Cyanobacteria contain a variety of pigment molecules, as shown in Table 1. As a result, the color of cyanobacteria cultures can vary significantly based on the relative amount of each pigment produced. A researcher placed a culture of cyanobacteria under green lights. Within a few weeks, the appearance of the cyanobacteria changed from green to red. The researcher claimed the color change in the culture was the result of an adaptation allowing greater photosynthesis. Which of the following provides the best reasoning to justify the researcher's claim?

in green light, more phycoerythin motecules are produced, allowing more green light to be absorbed, thus increasing photosynthesis