Question

directions: read each question carefully, and record your answers at the bottom of the paper. you may use your notes from your binder, but no phones, laptops, or any other electronic device may be used.

question 1:
a student made this model of a protein.
image of a protein model with connected shapes
which two statements describe how the model could be labeled?
a. each shape could be labeled an amino acid, and the links between the shapes could be labeled peptide bonds.
b. the entire structure could be labeled polysaccharide, and each shape could be labeled monosaccharide.
c. each shape could be labeled a nucleotide, and the entire structure could be labeled nucleic acid.
d. the entire structure could be labeled polymer, and each shape could be labeled a monomer.
e. the individual shapes could be labeled steroids and phospholipids, and the links between the shapes could be labeled peptide bonds.
f. each shape could be labeled dna, and the entire structure could be labeled rna.

question 2:
a student carried out an investigation to answer this question:
does a low-oxygen environment change the rate of photosynthesis?
what is the most probable explanation that the student will develop after completing his investigation?
a. oxygen is a reactant of photosynthesis, so low oxygen levels decrease the rate of photosynthesis.
b. oxygen is not required for photosynthesis to occur, so the rate of photosynthesis is unaffected by low oxygen levels.
c. oxygen supplies the energy that is stored in food molecules, so photosynthesis stops in conditions where oxygen is not plentiful.
d. the oxygen in the environment limits the rate of photosynthesis, so photosynthesis proceeds faster as oxygen levels decrease.

question 3:
which statement correctly compares the roles of different types of organic molecules in the body?
a. carbohydrates provide insulation for the body, while nucleic acids provide long term energy storage.
b. nucleic acids provide support and structure for the body, while carbohydrates provide insulation.
c. lipids provide long-term energy storage for the body, while carbohydrates provide quickly available energy.
d. proteins provide cushioning for organs, while lipids carry the bodys genetic information.

record answers here
1.
2.
3.

Explanation:

Question 1

• Proteins are polymers of amino acids linked by peptide bonds. Option A: Shapes (amino acids) + links (peptide bonds) matches protein structure.
• Option B: Polysaccharides are sugar polymers (monosaccharides), not protein.
• Option C: Nucleotides form nucleic acids, not protein.
• Option D: Polymer (protein) and monomer (amino acid) is correct, but the other part (steroids/phospholipids) is wrong. Wait, no—wait, the first part of D: "The entire structure could be labeled polymer, and each shape could be labeled a monomer" is correct for protein (polymer of amino acid monomers). But the second part of D: "The individual shapes could be labeled steroids and phospholipids" is wrong (those are lipids). Wait, original options: Let's recheck. Option A: Each shape (amino acid), links (peptide bonds) – correct for protein. Option D: Wait, no, the options:

Wait, the model is a protein. So:

• A: Amino acids (shapes) linked by peptide bonds – correct.
• D: Wait, no, D says "The entire structure could be labeled polymer, and each shape could be labeled a monomer" – protein is a polymer, amino acids are monomers – that's correct. But the other part of D: "The individual shapes could be labeled steroids and phospholipids, and the links between the shapes could be labeled peptide bonds" – no, steroids/phospholipids are lipids, not amino acids. So D is wrong. Wait, maybe I misread. Let's check again.

Wait, the options:

A. Each shape: amino acid, links: peptide bonds – correct (protein is amino acids linked by peptide bonds).

D. Entire structure: polymer (protein is a polymer), each shape: monomer (amino acid is monomer) – that's correct. But the second part of D: "The individual shapes could be labeled steroids and phospholipids" – no, that's wrong. Wait, maybe the option D is miswritten? Wait, the original question: "Which TWO statements..."

Wait, maybe I made a mistake. Let's recall: Proteins are polymers of amino acids (monomers) linked by peptide bonds. So A is correct (shapes = amino acids, links = peptide bonds). Then, is there another?

Wait, option D: "The entire structure could be labeled polymer, and each shape could be labeled a monomer" – that's correct (protein is a polymer, amino acids are monomers). But the other part of D: "The individual shapes could be labeled steroids and phospholipids, and the links between the shapes could be labeled peptide bonds" – no, steroids/phospholipids are lipids, not amino acids. So D is incorrect. Wait, maybe option A and... Wait, maybe I misread option D. Let me check again.

Wait, the options:

A. Each shape: amino acid, links: peptide bonds – correct.

D. The entire structure: polymer, each shape: monomer – correct (protein is polymer, amino acid is monomer). But the second part: "The individual shapes could be labeled steroids and phospholipids" – no, that's wrong. So maybe the correct two are A and... Wait, maybe option D's first part is correct, but the second part is a distractor? No, the option is a single statement. Wait, the question is "Which TWO statements..." So each option is a statement. Let's re-express:

• A: Correct (protein = amino acids + peptide bonds).
• B: Polysaccharide (carbohydrate) – wrong.
• C: Nucleotide (nucleic acid) – wrong.
• D: Entire structure (polymer) and each shape (monomer) – correct (protein is a polymer of amino acid monomers). But the second part: "The individual shapes could be labeled steroids and phospholipids" – no, that's lipids. So D is incorrect. Wait, maybe the option D is "The entire structure could be labeled polymer, and each shape could be l…

Photosynthesis reactants: CO₂ and H₂O; products: glucose and O₂. Oxygen is a product, not a reactant. So low oxygen (a product) doesn't affect photosynthesis rate. Option B states oxygen is not required for photosynthesis, so its level doesn't affect the rate – correct.

• A: Oxygen is a product, not reactant – wrong.
• C: Oxygen doesn't supply energy for photosynthesis (energy from light) – wrong.
• D: Oxygen isn't a limiting factor for photosynthesis (light, CO₂, H₂O are) – wrong.

• Lipids (fats) store long-term energy; carbohydrates (sugars) provide quick energy.
• A: Carbohydrates don't insulate, lipids do; nucleic acids don't store energy – wrong.
• B: Nucleic acids (DNA/RNA) store genetic info, not support; carbs don't insulate – wrong.
• C: Lipids (long-term energy), carbs (quick energy) – correct.
• D: Proteins cushion, but lipids don't carry genetic info (nucleic acids do) – wrong.

Answer:

1. A. Each shape could be labeled an amino acid, and the links between the shapes could be labeled peptide bonds.

D. The entire structure could be labeled polymer, and each shape could be labeled a monomer.

Question 2