Metabolism links building and breaking down
導入済み| English | 意味 |
|---|---|
| metabolism/məˈtæbəlɪzəm/ | 代謝 |
| urea/juːˈrɪə/ | 尿素 |
What would explain this observation?
- Digestion breaks some molecules down while cells build others. Metabolism 代谢 includes both directions, linked by enzymes, available materials and energy transfer.
- Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.
Build the model
- Metabolism is the sum of all reactions in a cell or body. Energy transferred by respiration supports continual enzyme-controlled processes that synthesize new molecules. It includes glucose conversion into starch, glycogen and cellulose; formation of a lipid from one glycerol molecule and three fatty-acid molecules; and amino acids joining to form proteins.
- metabolism: The sum of reactions in a cell or body; urea 尿素: A waste product formed during breakdown of excess proteins and excreted from the body.
Which statement correctly describes metabolism?
難易度 1/5 · 100 コイン + 今日初回完了時に小ボーナス付与
Metabolism is the sum of ALL chemical reactions in the body - synthesis (building proteins, lipids) and breakdown (respiration, digestion). It is not gut transit, and it includes respiration.
Match each technical term to its precise meaning.
難易度 2/5 · 140 コイン + 今日初回完了時に小ボーナス付与
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- In plants, glucose and nitrate ions provide materials for amino-acid production. Metabolism also includes respiration and the breakdown of excess proteins to form urea for excretion. Match each molecule to its role rather than treating every metabolic reaction as digestion or every product as an energy store. Urea formation and urea excretion are related but distinct processes.
- Build a concept map with reactants, products and functions. Use one arrow for a specified conversion and annotate any needed additional material, such as nitrate. Trace where a material comes from and where a waste goes. Do not add advanced reaction pathways or treat the lipid particle-ratio model as a complete biochemical mechanism.
Which two habits make the investigation or model in this case more defensible?
難易度 2/5 · 140 コイン + 今日初回完了時に小ボーナス付与
Stating the conditions and assumptions lets others repeat the work exactly, and recording the supporting evidence lets them check the conclusion. Hiding disagreeing results removes the evidence that could challenge a wrong conclusion, and one measurement can never establish a wider claim.
Work from known quantities
- State the known values and their units. Choose the relation because its assumptions fit this case, then rearrange before substitution.
- Known: the stated lipid-building model requires one glycerol and three fatty acids per lipid molecule. For 7 lipid molecules it needs 7 glycerol and 21 fatty-acid molecules. With 10 glycerol and 24 fatty acids, at most 8 lipid molecules can form in this model because fatty acids run out first, leaving 2 glycerol molecules unused.
In the stated model, each lipid needs three fatty acids. How many fatty-acid molecules are needed for 9 lipid molecules? Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
In the stated model, each lipid needs three fatty acids. How many fatty-acid molecules are needed for 9 lipid molecules?
難易度 2/5 · 140 コイン + 今日初回完了時に小ボーナス付与
The result is 27 molecules. Known: each lipid needs 3 fatty acids in this model. For 9 lipid molecules: 9 x 3 = 27 fatty-acid molecules. If a reactant runs short, it limits the product count, as the worked case shows.
Check the conclusion and its limits
- Metabolism includes synthesis and breakdown, not only reactions that release energy. Proteins are made from amino acids, while lipids use glycerol and fatty acids. Urea is a waste from excess protein breakdown and is not the same substance as glucose or lactic acid.
- Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.
Metabolism includes only reactions that break molecules down. This claim is false: Metabolism covers building reactions (synthesising proteins from amino acids) as well as breaking reactions. Defining it as breakdown alone would exclude all growth and repair chemistry.
Metabolism links building and breaking down: In plants, glucose and nitrate ions provide materials for amino-acid production. Metabolism also includes respiration and the breakdown of excess proteins to form urea for excretion. Match each molecule to its role rather than treating every metabolic reaction as digestion or every product as an energy store. Urea formation and urea excretion are related but distinct processes.
Metabolism includes only reactions that break molecules down.
難易度 1/5 · 100 コイン + 今日初回完了時に小ボーナス付与
Metabolism covers building reactions (synthesising proteins from amino acids) as well as breaking reactions. Defining it as breakdown alone would exclude all growth and repair chemistry.
The sum of reactions in a cell or body: write the technical term.
難易度 1/5 · 100 コイン + 今日初回完了時に小ボーナス付与
metabolism means The sum of reactions in a cell or body.