Metabolism 1 — Flashcards (Chemical Energy)

A comprehensive set of flashcards for reviewing key concepts related to metabolism and energy in biological systems.

What is energy?

The ability to do work or produce heat/light.

What are forms of energy?

Mechanical, electrical, chemical, thermal, nuclear, etc.

What type of energy do cells mainly use?

Chemical energy.

Where does our energy come from?

Food (originally from the sun).

What processes handle energy in the body?

Ingestion → digestion → circulation → transport to cells.

How many cells use energy in your body?

~37 trillion cells.

What is ATP?

The main energy molecule of the cell.

What does ATP do?

Stores and releases energy for cellular processes.

Where is ATP made?

Mitochondria.

What is ATP like?

A 'mini battery' for one reaction.

What happens when ATP releases energy?

ATP → ADP + energy.

How is ATP produced?

Using a proton (H⁺) gradient across the mitochondrial membrane.

What is this gradient like?

Like water behind a dam.

What is needed to make ATP?

Oxygen (O₂).

What is oxidation?

Loss of electrons.

What is the memory trick for oxidation/reduction?

OIL RIG (Oxidation Is Loss, Reduction Is Gain).

Why is oxidation important in metabolism?

It releases energy.

What are macronutrients?

Fats, carbohydrates, proteins.

What do macronutrients do?

Get oxidised to release energy.

What are micronutrients?

Vitamins and minerals.

Do micronutrients give energy?

No, but they help reactions.

What is metabolism?

All chemical reactions in a cell.

What are the two types of metabolism?

Anabolism and catabolism.

What is anabolism?

Builds molecules → requires energy.

What is catabolism?

Breaks down molecules → releases energy.

How are anabolism and catabolism linked?

Energy from catabolism powers anabolism.

What are activated carrier molecules?

Molecules that carry energy (e.g. ATP).

Examples of high-energy carriers?

ATP, NADH, FADH₂.

Examples of low-energy forms?

ADP, NAD⁺, FAD.

What is NADH?

An electron (energy) carrier.

What is NAD⁺?

Low-energy form of NADH.

What is FADH₂?

Another energy carrier.

What do NADH and FADH₂ carry?

Electrons (energy) and hydrogen.

What are the end products of catabolism?

CO₂, H₂O, NH₃.

What are building blocks for anabolism?

Amino acids, fatty acids, sugars.

What happens if energy intake is too high?

Obesity, diabetes.

What happens if energy intake is too low?

Malnutrition, starvation.

How can metabolism be controlled?

Substrate concentration, enzyme amount, enzyme activity, compartmentalisation.

How can enzyme activity be changed?

Covalent modification (e.g. phosphorylation), Allosteric regulation.

Do mitochondria have DNA?

Yes.

Where is mitochondrial DNA inherited from?

Mother.

Why is mitochondrial DNA useful?

Tracing maternal lineage.

What is the quick summary of ATP?

ATP = energy currency.

What does oxidation do?

Oxidation = releases energy.

What does catabolism do?

Catabolism = break → energy.

What does anabolism do?

Anabolism = build → needs energy.

What are NADH/FADH₂?

NADH/FADH₂ = energy carriers.

What are mitochondria known as?

Mitochondria = energy factory.