Biology 103 Chapter 5
Terms in this set (37)
Which organism depends on photosynthesis for its life?
a sea slug
-----All of the answer choices are correct.
an oak tree
Which of these organisms can carry out photosynthesis?
---plants, algae, and cyanobacteria
not an oxidation-reduction reaction.
----an energy transfer process that produces glucose and oxygen.
None of the answer choices are correct.
a set of reactions that produces water and carbon dioxide.
a chemical process not dependent on chlorophyll.
The reactant (reactants) of photosynthesis is (are)
water and carbon dioxide.
The main organic product of photosynthesis is
The main byproduct molecule of photosynthesis that is released into the environment is
The primary pigment molecule needed for photosynthesis is
Which of these groups represents organisms that are heterotrophs?
all organisms that developed after photosynthesis
microorganisms that harness solar energy, converting it to chemical energy
---non-photosynthesizing bacteria, fungi, earthworms
photosynthesizing bacteria, algae, ferns, pine trees
Organisms that make their own organic compounds from inorganic substances are called
Organisms that consume preexisting organic molecules are called
The proportion of oxygen in our atmosphere today
has increased to 20%, including rapid increase since water-splitting photosynthesis and eukaryotes.
Discrete packets of kinetic energy in light are called
The organelle that carries out photosynthesis in plants is the
In plant cells, a membrane studded with photosynthetic pigments in plant cells is the
Accessory pigments include molecules that reflect reds, oranges and yellows. Leaves of many plants show these colors in the fall because
the chlorophyll in the leaves degrades as winter approaches.
Photosystem II produces
---both oxygen and high-energy electrons.
Photosystem I initiates the electron transport chain that produces
The electrons flowing through the electron transport chains in photosynthesis come from ____ and end up being carried by _____.
Photosystem I and photosystem II are respectively part of
the light reactions and the carbon reactions.
----the light reactions only.
the carbon reaction and the light reactions.
the carbon reactions only.
The main organic molecule product of the carbon reactions is
The Calvin cycle
is a cyclic reactive pathway that produces three-carbon molecules from CO2.
Rubisco combines ribulose bisphosphate with carbon from
Which plants keep their stomata open only at night?
The carbon atoms in cellulose found in a log originally came from _____ absorbed by the plant.
carbon dioxide in the air,
Combustion is an inorganic chemical reaction, with the net result of burning a log being a reverse reaction from photosynthesis. What products would be formed in burning a log?
carbon dioxide and water
Before photosynthetic cells became abundant, _____ would not be widespread.
cells using anaerobic respiration
---cells using aerobic respiration
When a plant encounters hot, dry conditions of stress, the
stomata open, decreasing gas exchange.
stomata close, increasing gas exchange.
----stomata close, decreasing gas exchange.
stomata open, increasing gas exchange.
When NADP+ _____ in the light cycle it is ______ forming NADPH.
donates electrons; reduced
---accepts electrons; reduced
donates electrons; oxidized
accepts electrons; oxidized
Plants require a lot of water for hydration, metabolism, homeostasis, and photosynthesis. How is water used in photosynthesis?
as an electron donor in the photosystems
The role of water in photosystem I is in contributing electrons, hydrogens, and oxygen. The resulting electrons in photosystem I
prevent chlorophylls from losing all electrons and breaking apart as they capture light energy.
A plant performing photosynthesis will produce ____ and consume _____.
water; carbon dioxide
carbon dioxide; water
carbon dioxide; oxygen
---oxygen; carbon dioxide
Why is photorespiration more of a problem for a plant when their stomata are closed?
Oxygen, from water in photosystem I, can't leave the leaf, and competes with carbon dioxide for rubisco's active site.
How do C4 plants minimize photorespiration?
The light reactions and carbon reactions occur in different cells, so oxygen does not come into contact with rubisco.
How do CAM plants minimize photorespiration?
Stomata are only opened at night, storing carbon dioxide in malate. During the day the carbon dioxide is released for photosynthesis.
The sea slug Elysia chlorotica is green because it contains
The sea slug Elysia chlorotica absorbs chloroplasts from the alga Vaucheria litorea as it digests the cells. Thousands of structure and transport proteins involved in photosynthesis require thousands of genes in DNA. The algal chloroplast contains only 10% of the genes, while the algal nucleus contains the rest. Chloroplasts function inside the sea slug, allowing it to live on sunlight and carbon dioxide, suggesting that
regions of DNA containing necessary genes for photosynthesis must be present in sea slug cells to retain functioning chloroplasts.
When researchers Rumpho and Manhart looked at the genomes of sea slugs and chloroplasts, what hypothesis were they testing?
that some chloroplast genes were present in the sea slug chromosomes