Model Food Breakdown - Middle School Life Science

What are the two main products of cellular respiration besides energy in ATP?

Carbon dioxide and water. Glucose carbons become $CO_2$ ; oxygen combines with hydrogen forming $H_2O$ .
Which option correctly matches a polymer to its monomers: protein, starch, triglyceride?

Protein→amino acids; starch→glucose; triglyceride→fatty acids+glycerol. Each polymer breaks into its specific monomer units.
Which macromolecule is broken down into monosaccharides such as glucose?

Carbohydrates. Complex sugars break into simple sugars cells can absorb.
Identify the correct word equation for cellular respiration using glucose and oxygen.

Glucose + oxygen → carbon dioxide + water + ATP. Summarizes how cells extract energy from glucose using oxygen.
Which macromolecule is broken down into fatty acids and glycerol?

Lipids (fats and oils). Ester bonds in fats are hydrolyzed into smaller components.
What is the main monosaccharide cells use as a fuel for cellular respiration?

Glucose. Six-carbon sugar that cells break down for ATP energy.
What are the reactants of cellular respiration in a typical model?

Glucose and oxygen. These molecules enter the process to be broken down for energy.
What are the reactants in the word equation for cellular respiration?

Glucose and oxygen. These molecules enter the mitochondria to produce ATP.
What is the specific name for an enzyme that breaks down lipids?

Lipase. Breaks ester bonds in triglycerides during fat digestion.
Which process breaks large food molecules into smaller molecules that cells can absorb?

Digestion. Breaks down complex molecules into simple nutrients cells can use.
What is the term for the specific region of an enzyme where the substrate binds?

Active site. The pocket where substrate binds for catalysis to occur.
What is the main purpose of cellular respiration in cells?

To make ATP from food molecules. Breaks down glucose to release energy stored in chemical bonds.
Which statement best describes what happens to atoms during digestion and respiration?

Atoms are rearranged into new molecules; they are not destroyed. Conservation of matter: atoms recombine but aren't created or lost.
What is the term for a molecule that an enzyme acts on?

Substrate. The specific molecule that fits into an enzyme's active site.
Choose the correct model outcome: After digestion, what happens to amino acids in the body?

They are rearranged to build new proteins. Cells link amino acids with peptide bonds to form new proteins.
Identify the organelle where cells rearrange food molecules to make ATP.

Mitochondria. The powerhouse of the cell converts food to usable energy.
Which type of biological molecule is broken down into amino acids?

Proteins. Peptide bonds between amino acids are broken during protein digestion.
Which model statement correctly explains why oxygen is needed in cellular respiration?

Oxygen helps break down glucose so more ATP can be produced. Oxygen accepts electrons, allowing complete glucose breakdown.
What is the term for breaking large molecules into smaller molecules using water?

Hydrolysis. Water molecules split bonds between monomers in polymers.
What is the main purpose of digestion at the molecular level?

To break large food molecules into small absorbable molecules. Large molecules can't pass through cell membranes until broken down.
Which model correctly shows dehydration synthesis forming a polymer from monomers?

Many monomers → polymer + water. Shows water removal as monomers bond to form polymers.
Which atoms from oxygen gas end up in the water produced during cellular respiration?

Oxygen atoms from $O_2$ . Oxygen gas combines with hydrogen from glucose to form water.
Which process breaks molecules down and usually releases energy for the cell?

Catabolism. Breaking bonds releases energy stored in food molecules.
What are the products of cellular respiration in a typical model?

Carbon dioxide, water, and ATP. Glucose and oxygen atoms rearrange into these molecules.
What molecule is the immediate, usable energy currency produced from food energy in cells?

ATP. Adenosine triphosphate stores energy in phosphate bonds.
Which molecule is the immediate energy currency that cells make from food molecules?

ATP. Cells use ATP to power all energy-requiring processes.
Identify the correct model statement: Do enzymes change into products during digestion?

No; enzymes are not consumed in the reaction. Enzymes catalyze reactions but remain unchanged after.
What is the specific name for an enzyme that breaks down carbohydrates?

Amylase. Found in saliva and pancreas to digest starches.
Which cell structure is the main site of cellular respiration that releases energy from food?

Mitochondria. Powerhouse organelles that convert glucose to ATP energy.
Which process rearranges small molecules into larger molecules needed for growth and repair?

Biosynthesis (anabolism). Builds complex molecules from simple ones, requiring energy input.
What type of reaction joins monomers into a polymer by removing water?

Dehydration synthesis (condensation). Monomers link by removing H from one and OH from another.
Which cell organelle is the main site of cellular respiration in eukaryotic cells?

Mitochondria. The powerhouse organelle where ATP is produced from glucose.
Which process rearranges atoms from glucose and oxygen into carbon dioxide and water?

Cellular respiration. Chemical bonds break and reform to create new molecules.
What is the main product of carbohydrate digestion that cells commonly use for energy?

Glucose. A simple sugar that enters cellular respiration for ATP production.
Which atoms in glucose end up in the carbon dioxide produced during cellular respiration?

Carbon atoms from glucose. Six carbon atoms from $C_6H_{12}O_6$ form six $CO_2$ molecules.
Which macromolecule is broken down into amino acids during digestion?

Proteins. Peptide bonds between amino acids are broken by hydrolysis.
What is the term for building larger molecules by removing water?

Dehydration synthesis (condensation). Monomers join by releasing water molecules between them.
Identify the correct balanced chemical equation for cellular respiration.

$C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{ATP}$ . Shows glucose and oxygen rearranging into new molecules plus energy.
Which type of biological molecule is broken down into simple sugars such as glucose?

Carbohydrates. Complex carbs like starch break into glucose for cellular energy.
What are the products in the word equation for cellular respiration?

Carbon dioxide, water, and ATP (energy). Energy from glucose bonds is transferred to ATP bonds.
Which model correctly shows hydrolysis of a carbohydrate polymer into monomers?

Polymer + water → many monosaccharides. Shows water breaking glycosidic bonds in polysaccharides.
Which macromolecule is broken down into amino acids?

Proteins. Peptide bonds between amino acids are broken by hydrolysis.
Which statement best models matter: Are atoms destroyed when food is used for energy in cells?

No; atoms are rearranged into new molecules. Conservation of matter: atoms cannot be created or destroyed.
Identify the correct model idea: Are bonds broken, formed, or both in digestion?

Both; bonds are broken and new bonds can form. Hydrolysis breaks bonds; synthesis forms new ones.
Which type of biological molecule is broken down into fatty acids and glycerol?

Lipids (fats and oils). Triglycerides split into three fatty acids and one glycerol molecule.
What is the cell process that rearranges glucose and oxygen into ATP, $CO_2$ , and $H_2O$ ?

Cellular respiration. Breaks glucose bonds to release energy stored in them.
What type of reaction adds water to break a polymer into monomers?

Hydrolysis. Water is added to split chemical bonds between monomers.
Identify the correct pathway: What happens to excess glucose after immediate energy needs are met?

It can be stored as glycogen or converted to fat. Body stores excess energy as glycogen (short-term) or fat (long-term).
What is the specific name for an enzyme that breaks down proteins?

Protease. The suffix '-ase' indicates an enzyme for that substrate.
What is the term for breaking large food molecules into smaller molecules during digestion?

Chemical digestion (hydrolysis). Water molecules break bonds between monomers in polymers.
Which option best models digestion: Does it create new atoms or change how atoms are bonded?

It changes how atoms are bonded (breaks and reforms bonds). Enzymes break existing bonds without creating new atoms.
What is the monomer (building block) of proteins that can be rearranged to build new proteins?

Amino acids. Twenty different types combine in various sequences to form proteins.
What are enzymes, in the context of food molecule breakdown?

Proteins that speed up chemical reactions in digestion. Biological catalysts lower activation energy for reactions.
What is the main role of digestive enzymes in food breakdown?

They speed up chemical digestion reactions. Enzymes catalyze reactions without being consumed.

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