Photosynthesis and Cellular Respiration Vocabulary

Flashcards covering key vocabulary for photosynthesis and cellular respiration based on lecture notes.

Photoautotroph

An organism capable of undertaking photosynthesis.

Photosynthesis

The process of capturing light energy to power the production of glucose and oxygen from carbon dioxide and water.

Mesophyll cell

A plant cell type found in leaves that contains large amounts of chloroplasts.

Chloroplast

A membrane-bound organelle only found in plant and photoautotroph cells that is the site of photosynthesis.

Chlorophyll

A chemical found in the thylakoids of chloroplasts responsible for absorbing light energy in photosynthesis.

Stoma (pl. stomata)

A small pore on the leaf’s surface that opens and closes to regulate gas exchange.

Xylem

Vascular tissue in plants responsible for transporting water and minerals from the roots to the leaves.

Light-dependent stage

The first stage of photosynthesis, where light energy splits water molecules into oxygen and hydrogen inside the thylakoid membranes; also known as the light-dependent reactions.

Thylakoid

A flattened sac-like structure housed inside the chloroplast, made up of a chlorophyll-containing membrane enclosing a lumen; the location of the light-dependent stage of photosynthesis.

Granum (pl. grana)

A stack of thylakoids.

NADPH

A coenzyme that is a proton (H+) and electron carrier in photosynthesis.

ATP

Adenosine triphosphate, a high-energy molecule that, when broken down, provides energy for cellular processes.

Photolysis

The process in which molecules are broken down by the action of light.

Light-independent stage

The second stage of photosynthesis where carbon dioxide is used to form glucose in the stroma of a chloroplast; also known as the Calvin cycle, the dark stage, or the light-independent reactions.

Stroma

The fluid substance that makes up the interior of chloroplasts; the site of the light-independent stage of photosynthesis.

Rubisco

A pivotal enzyme involved in initial carbon fixation during the light-independent stage of photosynthesis.

Carbon fixation

The process in living organisms where inorganic carbon, typically within carbon dioxide, is converted into organic compounds such as glucose; a central part of the light-independent stage of photosynthesis.

Inorganic

A compound that does not contain a carbon-hydrogen bond, e.g., carbon dioxide.

Organic

A compound containing a carbon-hydrogen bond, e.g., glucose.

Substrate

The reactant of a reaction catalyzed by an enzyme.

Photorespiration

A wasteful process in plants initiated by Rubisco that limits photosynthesis.

Affinity

The tendency of a molecule/atom to bind or react with another molecule/atom.

C3 plants

Plants with no evolved adaptation to minimize photorespiration.

C4 plants

Plants that minimize photorespiration by separating initial carbon fixation and the remainder of the Calvin cycle over space.

Bundle-sheath cell

A plant cell type that is the site of most of the Calvin cycle in C4 plants.

CAM plants

Plants that minimize photorespiration by separating initial carbon fixation and the remainder of the Calvin cycle over time.

Optimal

The point at which, for a given condition (e.g., temperature), the maximum function of an enzyme occurs; also known as optimum.

Plateau

To reach a state where no further change occurs.

Saturation point

The point at which a substance (e.g., an enzyme) cannot receive more of another substance (e.g., a substrate).

Limiting factor

A factor that prevents the rate of reaction from increasing.

Limiting reagent

A reactant that prevents the rate of reaction from increasing.

Denature

The disruption of a molecule’s structure by an external factor such as heat.

Enzyme inhibitor

A molecule that binds to and prevents an enzyme from functioning.

Competitive inhibitor

A molecule that hinders an enzyme by blocking the active site and preventing the substrate from binding.

Non-competitive inhibitor

A molecule that hinders an enzyme by binding to an allosteric site and changing the shape of the active site to prevent the substrate from binding.

Allosteric site

A region on an enzyme that is not the active site.

Reversible inhibition

Enzyme inhibition that involves weaker bonds that can be overcome.

Irreversible inhibition

Enzyme inhibition that involves stronger bonds that cannot be broken.

CRISPR

Prokaryotes that protect themselves against viral invasion.

CRISPR-associated protein 9 (Cas9)

An endonuclease that creates a blunt end cut at a site specified by guide RNA (gRNA).

Genetic modification

The manipulation of an organism’s genetic material using biotechnology.

Genetically modified organism (GMO)

An organism with genetic material that has been altered using genetic engineering technology.

Arable land

Land that is suitable for growing crops.

Yield

The amount of agricultural product harvested per area of land.

Cellular respiration

The process by which cells create usable energy in the form of ATP from a series of biochemical reactions, involving the breakdown of glucose.

Glucose

A simple 6-carbon sugar molecule with the formula C6H12O6.

Aerobic cellular respiration

Cellular respiration that occurs in the presence of oxygen. It involves three stages, during which glucose and O2 are converted into ATP, CO2, and water.

Anaerobic fermentation

A metabolic pathway that occurs in the absence of oxygen. It involves glycolysis, followed by further reactions that convert pyruvate into lactic acid in animals, or ethanol and CO2 in yeast.

Glycolysis

The first stage of aerobic cellular respiration, in which glucose is converted to two pyruvate molecules.

Krebs Cycle

The second stage of aerobic cellular respiration, where multiple reactions occur to create ATP, NADH, FADH2, and the waste product CO2; also known as the citric acid cycle or TCA cycle.

Electron transport chain

The third stage of aerobic cellular respiration, in which a series of protein complexes embedded in the inner membrane of a mitochondrion harnesses the stored energy in NADH and FADH2 to generate large amounts of ATP.

Mitochondrion

Double-membrane-bound organelle that is the site of the second and third stages of aerobic cellular respiration.

Cytosol

Aqueous fluid that surrounds a cell’s organelles inside the plasma membrane.

Mitochondrial matrix

Space inside the inner membrane of a mitochondrion, site of the Krebs cycle.

Crista (pl. cristae)

Folds of the inner membrane of a mitochondrion. The site of the electron tranpsort chain

Pyruvate

A three-carbon molecule that can be formed from the breakdown of glucose via glycolysis.

Nicotinamide adenine dinucleotide (NAD)

A coenzyme that acts as a proton (H+) and electron carrier in cellular respiration. NAD can cycle between its NAD+ and NADH forms, depending on the reaction it takes part in.

Flavin adenine dinucleotide (FAD)

A coenzyme that acts as a proton (H+) and electron carrier in cellular respiration; FAD can cycle between its FAD and FADH2 forms, depending on the reaction it takes part in.

Coenzyme A

A large organic non-protein molecule that plays a key role in the modification of pyruvate to allow it to enter the Krebs cycle; also known as CoA.

Acetyl-CoA

The product of the link reaction where pyruvate is conjugated to coenzyme A, creating the primary input into the Krebs cycle.

ATP synthase

Enzyme in the inner mitochondrial membrane that uses the concentration gradient of H+ to synthesize ATP from ADP and Pi.

Yeast

Unicellular eukaryotic organisms from the kingdom Fungi

Lactic acid fermentation

The process of anaerobic fermentation in animals, where pyruvate produced via glycolysis is converted to lactic acid.

Lactic acid

A 3-carbon molecule, product of anaerobic fermentation in animals; also known as lactate.

Ethanol fermentation

Process of anaerobic fermentation in yeast by converting pyruvate into ethanol and CO2; also known as alcohol fermentation

Ethanol

Two carbon alcohol molecule, with carbon dioxide, produced by anaerobic fermentation in yeast, bacteria and plants.

Rate

The chemical reaction rate proceeds by

Biofuel

Fuel created from organic material known as biomass with renewable or fossil fuels.

Biomass

Organic material, such as plant material and animal waste that can be sourced from many of our existing industries (such as agriculture and forestry).

Non- renewable

An energy that is replenished at a slower rate than it is being used and will eventullay run out such as fossil fuels

Carbon Neurtal

State in which we can balance the amount of CO2 and carbon emissions into the atmosphere that is balance by a process such as photosynthesis.

Fermentation

The process of alcohol or anaerobic chemical breakdown of high-energy organic molecules via actions of enzymes. For many plants, fermentation involves the conversion of glucose to ethanol and carbon dioxide.

Bioethanol

A type of biofuel that is produced through anerobic fermentation of plant sugars, mostly derived from animal fats or oils and glycerol.

Hydrolysis

Digestion using water to break chemical substance of organic life using for breakdown for polymers. A substance or enzyme breakdown such as digestion by chemical hydrolysis by enzymes.