C1.3 HL only

Question 1

Chloroplast

Answer 1

a specialized organelle found in plant and algal cells, acting as the site of photosynthesis

Question 2

Chloroplast envelope

Answer 2

the double-membrane structure that surrounds a chloroplast, a type of plastid found in plant cells where photosynthesis takes place

Question 3

Stroma

Answer 3

the supporting tissue or matrix of an organ or cell, distinct from the functional cells

Question 4

thylakoid membrane

Answer 4

a highly folded, internal membrane system found within chloroplasts, specifically in plant and algal cells.These membranes are crucial for photosynthesis, containing the pigments, enzymes, and electron carriers needed for the light-dependent reactions

Question 5

light dependent reactions

Answer 5

the first stage of photosynthesis, where light energy is captured and converted into chemical energy in the form of ATP and NADPH

Question 6

light independent reactions

Answer 6

the second stage of photosynthesis.They occur in the stroma of chloroplasts and use the ATP and NADPH produced during the light-dependent reactions to convert carbon dioxide into glucose and other organic molecules

Question 7

photosystem II (PS II)

Answer 7

a protein complex found in the thylakoid membranes of chloroplasts in plants, algae, and cyanobacteria

Question 8

photosystem I (PS I)

Answer 8

a protein complex found in the thylakoid membranes of plants, algae, and cyanobacteria.It’s a key component in photosynthesis, responsible for capturing light energy and driving electron transfer across the membrane, ultimately contributing to the production of NADPH

Question 9

NADP

Answer 9

NADP stands fornicotinamide adenine dinucleotide phosphate.It’s a coenzyme, a molecule that helps enzymes function, particularly in redox reactions (reactions that involve the transfer of electrons)

Question 10

NADPH (reduced NADP)

Answer 10

nicotinamide adenine dinucleotide phosphate, a crucial molecule involved in various cellular processes, particularly in anabolic reactions and as a reducing agent.It’s essential for building molecules like lipids and nucleic acids, and in plants, it plays a vital role in photosynthesis

Question 11

photolysis

Answer 11

the process where light energy is used to break down a molecule, most commonly water (H₂O), into smaller components

Question 12

array

Answer 12

a systematic arrangement of elements, often in rows and columns, on a solid support.

Question 13

accessory pigments

Answer 13

light-absorbing compounds, other than chlorophyll a, found in photosynthetic organisms.They broaden the range of light wavelengths that can be used for photosynthesis, by absorbing light that chlorophyll a doesn’t efficiently absorb and transferring that energy to chlorophyll a

Question 14

primary pigment

Answer 14

the main pigment involved in a specific biological process, such as photosynthesis.In plants, the primary pigment is chlorophyll a, which absorbs light energy to initiate photosynthesis, the process by which plants convert light energy into chemical energy

Question 15

Plastoquinone (PQ)

Answer 15

a terpenoid-quinone (meroterpenoid) molecule involved in the electron transport chain in the light-dependent reactions of photosynthesis

Question 16

Cytochrome complex (b6f)

Answer 16

a crucial protein complex found in the thylakoid membranes of chloroplasts in plants, green algae, and cyanobacteria.It plays a vital role in oxygenic photosynthesis by facilitating electron transfer between photosystem II (PSII) and photosystem I (PSI)

Question 17

proton pump

Answer 17

a type of membrane protein that uses energy to transport protons (hydrogen ions) across a cellular membrane, creating a proton gradient

Question 18

ATP synthase

Answer 18

a protein complex enzyme found in cellular membranes, particularly in mitochondria and chloroplasts, that synthesizes ATP (adenosine triphosphate)

Question 19

cyanobacteria

Answer 19

a type of photosynthetic bacteria.They are prokaryotic organisms, meaning they lack a nucleus and other membrane-bound organelles, but they contain chlorophyll and carry out oxygenic photosynthesis, producing oxygen as a byproduct

Question 20

mass extinction

Answer 20

a period in Earth’s history when a large number of species, often a significant percentage of all species, disappear in a relatively short geological time span

Question 21

non-cyclic photophosphorylation

Answer 21

a light-dependent reaction in photosynthesis where electrons flow in a linear pathway from water to photosystem II, then to photosystem I, and finally to NADP+, producing ATP and NADPH

Question 22

cyclic photophosphorylation

Answer 22

a part of photosynthesis where light energy is used to generate ATP (adenosine triphosphate) through a circular flow of electrons within Photosystem I (PSI)

Question 23

carbon fixation

Answer 23

the biological process where inorganic carbon (like carbon dioxide) is converted into organic compounds, primarily carbohydrates, by living organisms

Question 24

Ribulose bisphsphate (RuBP)

Answer 24

a five-carbon sugar molecule that plays a crucial role in photosynthesis, specifically in the Calvin cycle

Question 25

glycerate-3-phosphae (GP)

Answer 25

a chemical intermediate in the glycolysis metabolic pathway and light-independent reactions

Question 26

Triose phosphate (TP)

Answer 26

a three-carbon sugar molecule that is an important intermediate in both photosynthesis and glycolysis

Question 27

glycosidic bond

Answer 27

a type of covalent bond that joins a carbohydrate (sugar) molecule to another group, which can be another carbohydrate or a non-carbohydrate

Question 28

sucrose

Answer 28

a disaccharide, commonly known as table sugar, composed of the monosaccharides glucose and fructose

Question 29

phloem

Answer 29

a vascular tissue in plants responsible for transporting sugars and other organic compounds from where they are made (usually leaves) to other parts of the plant, like roots, stems, and developing fruits

Question 30

translocation

Answer 30

the movement of substances from one location to another. It has two main contexts: in plants, it's the movement of sugars (assimilates) through the phloem

Question 31

glycerol

Answer 31

a simple three-carbon molecule with three hydroxyl (-OH) groups attached. It's a key component of lipids (fats and oils) and serves as the backbone to which fatty acids are esterified to form triglycerides