Biology Quarter 2 flashcards (Don't let me down)

Citric Acid Cycle

Also known as the Krebs cycle or the TCA cycle, it is a series of chemical reactions that occur in the mitochondria of eukaryotic cells.

Cellular Respiration

The process of converting glucose into ATP (adenosine triphosphate), the energy currency of the cell, in which the citric acid cycle plays a crucial role.

Acetyl-CoA Formation

derived from the breakdown of glucose or fatty acids, combines with oxaloacetate to form citrate.

Citrate Isomerization

Citrate is converted to its isomer, isocitrate.

Isocitrate Oxidation

Isocitrate is oxidized, producing alpha-ketoglutarate, NADH, and CO2.

Alpha-Ketoglutarate Oxidation

Alpha-ketoglutarate is oxidized, producing NADH, CO2, and ATP.

Succinyl-CoA Formation

Alpha-ketoglutarate is converted to succinyl-CoA, generating NADH and CO2.

Succinate Formation

Succinyl-CoA is converted to succinate, producing ATP and CoA.

Fumarate Formation

Succinate is oxidized, generating FADH2 and fumarate.

Malate Formation

Fumarate is converted to malate, producing NADH.

Oxaloacetate Regeneration

Malate is oxidized, regenerating oxaloacetate and producing NADH.

Aerobic Respiration

A set of metabolic reactions that occur in the presence of oxygen in a cell to convert chemical energy into ATPs.

Electron Acceptor

A molecule that accepts electrons during a redox reaction, such as oxygen in aerobic respiration and sulfate ion or nitrate ion in anaerobic respiration.

Mitochondria

Organelles found in eukaryotic cells where aerobic respiration takes place.

Anaerobic Respiration

A process of cellular respiration where the high energy electron acceptor is neither oxygen nor pyruvate derivatives.

Low Oxygen Environment

A condition in which anaerobic respiration occurs due to a lack of oxygen.

End Products

The final substances produced in a metabolic process, such as carbon dioxide, water, and energy in aerobic respiration, and acids, alcohols, gases, and energy in anaerobic respiration.

Incomplete Oxidation

The partial breakdown of carbohydrates during anaerobic respiration.

Primitive Prokaryotes

Simple organisms that lack a nucleus and other membrane-bound organelles, and can perform anaerobic respiration.

Adenosine Triphosphate (ATP)

A molecule composed of an adenine molecule bonded to the sugar molecule ribose, which stores and releases energy for cellular reactions.

Photosynthesis

The process by which plants, algae, and some bacteria convert light energy into chemical energy in the form of sugars and oxygen.

Light-Dependent Reaction

The first stage of photosynthesis where light energy is absorbed by photosystem II and photosystem I to produce ATP, NADPH, and oxygen.

Stroma

The site of the dark reaction in photosynthesis, where carbon dioxide is converted into glucose.

Chemiosmosis

The process in which the movement of protons down their concentration gradient across a membrane is coupled to the synthesis of ATP.

Krebs Cycle

A series of reactions in aerobic respiration that produces ATP and carbon dioxide.

Fermentation

Anaerobic pathways that oxidize glucose to generate ATP energy using an organic molecule as the ultimate hydrogen acceptor.

Lactic Acid Fermentation

A type of fermentation that occurs in muscle cells when oxygen is limited, leading to the production of lactic acid and muscle soreness.

Oxygen Toxicity

The harmful effects of high levels of oxygen on cells, which can be reduced by anaerobic respiration.

Survival

The ability of organisms to live and reproduce in their specific habitats, which can be facilitated by anaerobic respiration in oxygen-limited environments.

Calvin Cycle

The set of chemical reactions that occur during photosynthesis, converting carbon dioxide and other compounds into glucose in the stroma.

Light-Independent Reaction

The phase of photosynthesis where the Calvin Cycle takes place, independent of light.

Rubisco

A plant enzyme that catalyzes the fixation of atmospheric carbon dioxide during photosynthesis and the reaction between carbon dioxide and RuBP.

Ribulose Bisphosphate

An organic substance involved in photosynthesis that reacts with carbon dioxide to form 3-PGA.

Fixation

The first stage of the Calvin Cycle where RuBisCO catalyzes the reaction between carbon dioxide and RuBP, forming a six-carbon compound that is converted into two three-carbon compounds.

Reduction

The second stage of the Calvin Cycle where ATP and NADPH use their stored energy to convert the three-carbon compound, 3-PGA, into another three-carbon compound called G3P.

Regeneration

The third stage of the Calvin Cycle where one G3P molecule leaves the cycle and contributes to the formation of carbohydrate molecules, commonly glucose (C6H12O6).

Carbon fixation

The process in the Calvin Cycle where carbon dioxide is converted into organic compounds.

ATP

a molecule that stores and releases energy for cellular processes.

NADPH

a molecule that carries high-energy electrons used in the reduction reactions of the Calvin Cycle.

Light-Dependent Reactions

The first stage of photosynthesis where solar energy is converted into chemical energy.

Photosystems

Structures in the thylakoid membranes where light-dependent reactions occur.

Pigment Molecule

Molecules that absorb photons of light, exciting electrons in the photosystem.

Electron Transport Chain

A series of molecules that transfer free electrons, generating energy for membrane pumps.

Hydrogen Ion Concentration Gradient

The difference in hydrogen ion concentration across the thylakoid membrane, used to generate ATP through chemiosmosis.

Hydrolysis

The process of breaking down water molecules to provide electrons, protons, and oxygen during photosynthesis.

ATP and NADPH

Energy carrier molecules that absorb and store energy during the light-dependent reactions.

Chemiosmosis

The process of using the hydrogen ion concentration gradient to generate ATP.

NADPH Generation

The formation of NADPH from NADP+ and hydrogen ions, fueled by the energy carried by electrons.

Energy Carriers

Molecules that store solar energy and can be used to produce sugar molecules.

Photosynthesis

The process of converting light energy into chemical energy stored in sugar and other molecules.

Heterotrophic nutrition

Acquiring energy by relying on compounds produced by other organisms.

Autotrophic nutrition

Producing one's own food without the help of other organisms.

Photoautotrophs

Organisms, such as plants, that use light as a source of energy to synthesize organic substances.

Chloroplasts

Organelles responsible for photosynthesis in plants, containing a double membrane and a thick fluid called the stroma.

Stroma

The thick fluid within the inner membrane of chloroplasts.

Thylakoids

Interconnected membranous sacs suspended in the stroma, enclosing the thylakoid space.

Thylakoid space

The compartment enclosed by thylakoids.

Grana

Stacks of thylakoids found in some places.

Chlorophyll

A green pigment residing in the thylakoid membranes, responsible for absorbing light.

Photosystems

Groups of pigments and proteins in the thylakoid membranes, responsible for the initial reactions of photosynthesis.

ATP

is an organic molecule used for short-term energy storage and transport in the cell.

ATP Hydrolysis

The process of breaking down ATP into ADP (Adenosine Diphosphate) and inorganic phosphate (Pi) through the reaction with water, releasing energy.

ATP Regeneration

The reversible process of recharging ADP to ATP, similar to a rechargeable battery, to be used as a power source for cellular processes.

Energy Coupling

The transfer of energy from an energetically favorable reaction (exergonic) like ATP hydrolysis to an energetically unfavorable reaction (endergonic) like ATP regeneration.

Exergonic Reaction

A reaction where energy is released to the surroundings, with the bonds being formed stronger than the bonds being broken.

Endergonic Reaction

A reaction where energy is absorbed from the surroundings, with the bonds being formed weaker than the bonds being broken.

Glycolysis

A cellular process where glucose is broken down to produce ATP.

TCA Cycle

Also known as the citric acid cycle or Krebs cycle, it is a series of chemical reactions that generate energy through the oxidation of acetyl-CoA.

Oxidative Phosphorylation

The process of generating ATP through the transfer of electrons in the electron transport chain.

Peptide Bond Formation

The process of joining amino acids together to form proteins, powered by ATP.

Pigments

Colorful compounds that absorb light from the sun.

Chlorophyll

The green pigment found in green plants that is responsible for their green color.

Chlorophyll a

The core pigment that absorbs sunlight for light-dependent photosynthesis.

Accessory pigments

Other pigments found in leaves that absorb light wavelengths that chlorophyll cannot effectively absorb.

Chlorophyll b

A pigment structurally similar to chlorophyll a but with a different absorption spectrum.

Carotenoids

Pigments that absorb light from violet to greenish-blue range and appear in shades of yellow or yellow-orange.

Anthocyanins

Pigments that give color to flowers, leaves, and fruits but do not participate in photosynthesis.

Xanthophylls

Pigments that pass along light energy to chlorophyll a and act as antioxidants.

Mesophyll cells

The photosynthetic cells in plant leaves.

Chloroplasts

Organelles found in mesophyll cells where photosynthetic pigments are located.