34. Lignin's role in plant transition from aquatic to terrestrial environments was to:
(A) protect early aquatic plants only in freshwater.
(B) allow plants to grow tall with rigid stems, providing structural support against gravity.
(C) serve as a cuticle component preventing any water loss.
(D) be primarily responsible for vibrant flower colors.
(E) significantly decrease photosynthetic efficiency.

30. In gymnosperm reproduction, the male gametophyte is: (A) a pollen grain enclosed within a tough wall. (B) where sperm fertilizes eggs within the female structure. (C) a free-living gametophyte developed from released spores. (D) a nucleus released freely into the ovule without a pollen tube. (E) an ovule maturing into a fruit after fertilization.

31. A key difference in seed protection and developmental between angiosperms and gymnosperms is that: (A) Angiosperm seeds develop exposed on cone scales, while gymnosperm seeds are enclosed in fruits. (B) Both produce seeds that are fully exposed to the environment at all stages. (C) Angiosperm seeds develop enclosed within a fruit, while gymnosperm seeds develop exposed on cones or modified leaves. (D) Gymnosperm seeds require animal dispersal within fruits, unlike angiosperms. (E) Angiosperms produce naked seeds, whereas gymnosperms always have seeds protected by an ovary.

32. Which accurately describes a key structural component or function within a typical vascular plant? (A) Water undergoes active transport through xylem to defy gravity. (B) Stomata, mainly on leaf undersides, regulate gas exchange and transpiration. (C) The cambium enables secondary growth, decreasing stem/root girth. (D) Root mineral uptake relies solely on soil concentration gradient. (E) Flowers are reproductive structures that prevent sexual reproduction.

33. Cellulose is a polysaccharide that is a major component of: (A) animal cell membranes. (B) fungal cell walls. (C) plant cell walls. (D) bacterial capsules. (E) insect exoskeletons.

35. Which statement is accurate regarding metabolism? (A) Energy from exergonic reactions is never coupled to drive endergonic reactions. (B) Endergonic reaction products have less potential energy, releasing energy. (C) Metabolism encompasses all chemical reactions, where exergonic energy (via ATP) drives endergonic. (D) Cellular respiration is exergonic, but it does not store energy in ATP. (E) Photosynthesis is an exergonic process that breaks down energy-rich molecules.

36. Which statement accurately describes the processes of photosynthesis? (A) Initial light-capturing reactions occur in thylakoid membranes, converting light into ATP/NADPH, releasing oxygen. (B) Splitting carbon dioxide releases oxygen as a byproduct. (C) Carbon fixation (Calvin cycle) takes place in the cytoplasm. (D) Electrons from chlorophyll go directly to ATP synthase. (E) Cellular respiration exclusively sustains light-independent reactions during night.

37. In photosynthesis, the splitting of water molecules (photolysis) directly contributes to the production of: (A) glucose and carbon dioxide. (B) ATP and NADPH for the Calvin cycle. (C) electrons, protons (H+), and oxygen gas. (D) pigments within the thylakoid membrane.. (E) ATP only, without NADPH.

38. The Calvin cycle (light-independent reactions) in photosynthesis primarily involves: (A) capturing light energy independently from water splitting. (B) producing ATP and NADPH from light energy. (C) converting carbon dioxide into sugars using ATP and NADPH. (D) releasing oxygen as a byproduct. (E) occurring exclusively during the night.

39. Which statement accurately describes key conceptual aspects of cellular respiration? (A) Glycolysis is a universal process that occurs with or without oxygen, serving as glucose's initial breakdown. (B) Pyruvate oxidation and citric acid cycle fully oxidize all oxygen atoms from glucose. (C) Oxidative phosphorylation uses ATP and FADH2 energy to produce NADH via single-step redox reactions. (D) The electron transport chain creates a sugar gradient for ATP synthesis. (E) Most aerobic ATP is produced exclusively in glycolysis.

40. Most of the ATP generated during aerobic cellular respiration is produced during: (A) glycolysis. (B) pyruvate oxidation. (C) the citric acid cycle. (D) oxidative phosphorylation. (E) fermentation.