Question

read the given clues and fill your answers in the boxes appropriately.
across

1. an example of anabolic reaction.
2. an enzyme for the digestion of starch.

down

1. an example of regulatory enzyme.
2. an example of catabolic reaction.

Answer:

For Clue 3 (Across: An example of anabolic reaction)

Anabolic reactions build complex molecules from simpler ones. Photosynthesis is a classic anabolic reaction where plants use carbon dioxide and water (simple molecules) to build glucose (a complex molecule) using light energy. The length of the answer (based on the grid for 3 across, let's assume the number of boxes: looking at the grid, 3 across has multiple boxes, and "photosynthesis" fits in terms of the concept. If we count the boxes for 3 across, let's see the grid: 3 across starts at box 3, and the horizontal row has, from the left, box 3, then several more. Let's confirm the length: "photosynthesis" has 12 letters? Wait, no, photosynthesis is P-H-O-T-O-S-Y-N-T-H-E-S-I-S? Wait, no, correct spelling: P-H-O-T-O-S-Y-N-T-H-E-S-I-S? Wait, no, photosynthesis is spelled P-H-O-T-O-S-Y-N-T-H-E-S-I-S? Wait, no, let's check: P (1), H (2), O (3), T (4), O (5), S (6), Y (7), N (8), T (9), H (10), E (11), S (12), I (13), S (14)? No, that's wrong. Wait, correct spelling: P-H-O-T-O-S-Y-N-T-H-E-S-I-S? No, I'm making a mistake. Wait, photosynthesis: P (1), H (2), O (3), T (4), O (5), S (6), Y (7), N (8), T (9), H (10), E (11), S (12), I (13), S (14)? No, that's 14 letters. Wait, maybe the answer is "photosynthesis" or maybe a shorter term? Wait, another anabolic reaction example: protein synthesis? But length? Alternatively, maybe "glycogenesis" (formation of glycogen from glucose, anabolic). Glycogenesis has 11 letters. Let's check the grid for 3 across: the horizontal row (3 across) intersects with 2 down, 1 down, etc. Let's assume the number of boxes for 3 across: looking at the image, the horizontal line (3 across) has, from the left, box 3, then a series of boxes up to the vertical column (1 down). Let's count the boxes for 3 across: the first box is 3, then the next boxes: let's see, the horizontal row (3 across) has, from box 3 to the right, how many? Let's see the vertical column (1 down) has 10 boxes (from top to bottom: 1, then 9 more? Wait, the vertical column (1 down) has box 1 at the top, then several down. The horizontal row (3 across) crosses the vertical column (1 down) at some point. Let's focus on the clue: anabolic reaction example. The most common example is photosynthesis. Let's check the length: "photosynthesis" has 12 letters? Wait, no, P-H-O-T-O-S-Y-N-T-H-E-S-I-S: that's 14 letters? Wait, no, I'm misspelling. Correct spelling: P (1), H (2), O (3), T (4), O (5), S (6), Y (7), N (8), T (9), H (10), E (11), S (12), I (13), S (14). Yes, 14 letters. If the 3 across grid has 12 or 14 boxes, then photosynthesis fits.

For Clue 4 (Across: An enzyme for the digestion of starch)

Starch is digested by amylase. Salivary amylase (in mouth) or pancreatic amylase (in small intestine) breaks down starch into smaller sugars. "Amylase" has 7 letters. Let's check the 4 across grid: the 4 across starts at box 4, and the horizontal row (4 across) has, from the left, box 4, then several boxes. The length of "amylase" is 7, which fits if the 4 across grid has 7 boxes.

For Clue 1 (Down: An example of regulatory enzyme)

Regulatory enzymes control metabolic pathways. Phosphofructokinase (PFK) is a key regulatory enzyme in glycolysis, but it's long. Alternatively, allosteric enzymes are regulatory, but "allosteric" is an adjective. Wait, a specific example: hexokinase (regulatory in glycolysis), but length? Alternatively, "cAMP-dependent protein kinase" is too long. Wait, maybe "phosphatase" or "kinase" but more specific. Wait, a common regulatory enzyme example is phosphofructokinase-1 (PFK-1), but that's long. Alternatively, maybe "aspartate transcarbamoylase" (ATCase), but too long. Wait, maybe the answer is "allosteric" (but it's an enzyme type, not a specific enzyme). Wait, maybe the question expects a shorter example. Alternatively, "trypsin" is a digestive enzyme, not regulatory. Wait, regulatory enzymes: enzymes that are regulated by allosteric effectors, covalent modification, etc. A common example is phosphofructokinase (PFK). Let's check the length: P-F-O-S-P-H-O-F-R-U-C-T-O-K-I-N-A-S-E? No, P-H-O-S-P-H-O-F-R-U-C-T-O-K-I-N-A-S-E? No, correct spelling: phosphofructokinase: P-H-O-S-P-H-O-F-R-U-C-T-O-K-I-N-A-S-E? Wait, no, phosphofructokinase is spelled P-H-O-S-P-H-O-F-R-U-C-T-O-K-I-N-A-S-E? No, I'm overcomplicating. Let's think of a shorter example. Maybe "kinase" is too vague. Alternatively, the answer is "phosphatase" (regulatory in some pathways), but length? The 1 down grid: box 1 is at the top, and the vertical column (1 down) has, from top to bottom, box 1, then several boxes. Let's assume the length: if 1 down has, say, 10 boxes, then "phosphofructokinase" is too long. Maybe the answer is "allosteric" (but it's not an enzyme, it's a type of regulation). Wait, maybe the question has a simpler answer. Let's recall: regulatory enzymes are often allosteric. Maybe the answer is "allosteric" but that's not an enzyme. Wait, maybe the example is "cAMP-dependent protein kinase" but that's too long. Alternatively, maybe the answer is "hexokinase" (regulatory enzyme in glycolysis, catalyzes first step, regulated by glucose-6-phosphate). Hexokinase has 9 letters. Let's check the 1 down grid: box 1 (top), then the vertical column. If 1 down has, say, 9 boxes, then hexokinase fits.

For Clue 2 (Down: An example of catabolic reaction)

Catabolic reactions break down complex molecules into simpler ones. Glycolysis is a classic catabolic reaction where glucose (complex) is broken down into pyruvate (simpler). "Glycolysis" has 8 letters. Let's check the 2 down grid: box 2 is at the top, vertical column. If 2 down has 8 boxes, then glycolysis fits.

For Clue 4 (Across: An enzyme for the digestion of starch)

As mentioned, amylase (salivary amylase or pancreatic amylase) digests starch. "Amylase" has 7 letters. Let's confirm: amylase breaks down starch into maltose (disaccharide) and smaller dextrins. The 4 across grid: box 4 (left), then horizontal boxes. If 4 across has 7 boxes, then amylase fits.

Final Answers (Filling the Grid)

• 3 Across (Anabolic reaction example): PHOTOSYNTHESIS (assuming the grid has enough boxes; if not, maybe GLYCOGENESIS, but photosynthesis is the most common example)
• 4 Across (Starch-digesting enzyme): AMYLASE
• 1 Down (Regulatory enzyme example): HEXOKINASE (or another appropriate regulatory enzyme; if length is an issue, maybe ALLOSTERIC but that's not an enzyme, so better HEXOKINASE)
• 2 Down (Catabolic reaction example): GLYCOLYSIS

Step-by-Step for Each Clue (Using Step-by-Step Format for Clarity)

Clue 3 (Across: Anabolic Reaction Example)

Step 1: Recall Anabolic Reaction Definition

Anabolic reactions build complex molecules from simpler ones.

Step 2: Identify Common Example

Photosynthesis (plants build glucose from CO₂ and H₂O) is a key anabolic reaction.

Step 3: Check Grid Length (Assumed)

If the 3 across grid has ~12–14 boxes, "photosynthesis" (14 letters) fits.

Clue 4 (Across: Starch-Digesting Enzyme)

Step 1: Recall Starch Digestion

Starch is digested by enzymes that break it into sugars (e.g., maltose).

Step 2: Identify Enzyme

Amylase (salivary or pancreatic) is the primary enzyme for starch digestion.

Step 3: Check Grid Length

"Amylase" has 7 letters, fitting a 7-box grid for 4 across.

Clue 1 (Down: Regulatory Enzyme Example)

Step 1: Recall Regulatory Enzyme Role

Regulatory enzymes control metabolic pathway rates (e.g., allosteric, covalent regulation).

Step 2: Identify Example

Hexokinase (regulates glycolysis, inhibited by glucose-6-phosphate) is a regulatory enzyme.

Step 3: Check Grid Length

"Hexokinase" has 9 letters, fitting a 9-box grid for 1 down.

Clue 2 (Down: Catabolic Reaction Example)

Step 1: Recall Catabolic Reaction Definition

Catabolic reactions break complex molecules into simpler ones (releasing energy).

Step 2: Identify Common Example

Glycolysis (breaks glucose into pyruvate) is a classic catabolic reaction.

Step 3: Check Grid Length

"Glycolysis" has 8 letters, fitting an 8-box grid for 2 down.

Filled Grid (Summary)

• 3 Across: PHOTOSYNTHESIS
• 4 Across: AMYLASE
• 1 Down: HEXOKINASE
• 2 Down: GLYCOLYSIS

(Note: The exact grid length may vary, so adjust the answer to match the number of boxes. For example, if 3 across has fewer boxes, "glycogenesis" (11 letters) or another shorter anabolic example could be used.)