Grade 11 Sports Science: Nutrition, Physiology, and Bioenergetics

Vocabulary practice flashcards generated for Grade 11 Sports Science, covering biological hierarchy, macronutrients, micronutrients, deficiency profiles, mass unit conversions, fibre breakdown, gastrointestinal pathways, muscle bioenergetics, ATP hydrolysis, calorimetry, and sports nutrition strategies.

Element

Pure chemical substances that cannot be broken down any further by chemical processes or chemical means (e.g., Carbon $C$, Hydrogen $H$, Oxygen $O$, Nitrogen $N$, Calcium $Ca$, Iron $Fe$).

Molecule

Two or more chemical elements chemically bonded together (e.g., Glucose $C_6H_{12}O_6$, Water $H_2O$).

Nutrient

Substances within food that provide energy, structural components, and essential physiological regulation in the human body.

Food

Any complex substance eaten or drunk by an organism to supply nutrients and energy to sustain life, repair tissues, and drive performance.

Systemic Hierarchy & Flow Model

The multi-stage organizational and physiological pathway linking chemical elements to whole food ingestion, digestion, absorption, cell repair, ATP generation, and athletic performance.

Golden Rule of Nutrient Classification

The terms "Macro" and "Micro" refer strictly to the quantity/amount required per day by the human body (grams vs. milligrams/micrograms), NOT their biological importance.

Carbohydrates

The primary fast-fuel macronutrient source for muscle contractions and brain/CNS function during moderate-to-high intensity exercise, yielding $4\,kcal/g$ ($\sim 17\,kJ/g$).

Proteins

Macronutrients primarily used to build and repair muscle tissue, form biological enzymes, produce hormones, and support immune function, yielding $4\,kcal/g$ ($\sim 17\,kJ/g$).

Fats (Lipids)

Dense macronutrients providing long-term energy reserves, cell membrane structure, protection of vital organs, insulation, and transport of fat-soluble vitamins, yielding $9\,kcal/g$ ($\sim 39\,kJ/g$).

Fat-Soluble Vitamins

Organic micronutrients stored in body fat tissues, comprising Vitamin A (vision/cell growth), Vitamin D (calcium absorption/bone health), Vitamin E (antioxidant protection), and Vitamin K (blood clotting).

Water-Soluble Vitamins

Organic micronutrients that cannot be stored in the body and must be ingested daily with excess excreted in urine, comprising B-Complex vitamins and Vitamin C.

Vitamin C (Ascorbic Acid)

A water-soluble vitamin essential for collagen synthesis, immune white blood cell activity, antioxidant defense, and plant-based iron absorption that cannot be stored or synthesized by humans.

Scurvy

A clinical deficiency state caused by prolonged absence of Vitamin C, characterized by collapsed collagen cross-linking, bleeding gums, petechiae, slow wound healing, joint pain, and tissue breakdown.

Iron ($Fe$)

An essential mineral forming the core active site of haemoglobin in red blood cells to bind and transport oxygen ($O_2$) from lungs to working muscle mitochondria.

Iron-Deficiency Anaemia

A clinical deficiency state where reduced iron leads to impaired haemoglobin production and oxygen transport, causing chronic fatigue, muscle weakness, dyspnoea, pale skin, and tachycardia during exertion.

Unit Conversion Rules for Mass

To convert from a larger mass unit to a smaller unit ($g \rightarrow mg \rightarrow \mu g$), multiply by $1,000$; to convert from a smaller unit to a larger unit ($\mu g \rightarrow mg \rightarrow g$), divide by $1,000$.

Dietary Fibre

Complex plant-derived carbohydrates that human digestive enzymes cannot digest or absorb, passing through the gastrointestinal tract largely intact.

Soluble Dietary Fibre

A type of fibre that dissolves in water to form a gel-like substance (found in oats, apples, beans), which binds bile acids to lower blood cholesterol and slows glucose absorption.

Insoluble Dietary Fibre

A type of fibre that does not dissolve in water (found in whole wheat, bran, vegetable stalks), adding physical bulk to stool, stimulating intestinal peristalsis, and preventing constipation.

Mitochondrion

The sub-cellular organelle ("Powerhouse of the Cell") that utilizes glucose, fatty acids, amino acids, and oxygen ($O_2$) to perform aerobic cellular respiration and generate ATP.

Sarcoplasmic Reticulum (SR)

A sub-cellular muscle organelle that stores Calcium ions ($Ca^{2+}$) at rest and rapidly releases them into the sarcoplasm following neural action potentials to trigger muscle contraction.

Sliding Filament Theory

The mechanism of muscle contraction where released $Ca^{2+}$ uncovers binding sites on Actin, allowing Myosin heads bound to ATP to attach and undergo a power stroke.

ATP Hydrolysis Reaction

The chemical reaction $ATP + H_2O \rightarrow ADP + Pi + \text{Energy}$, releasing approximately $7.3\,kcal/mol$ ($\sim 30.5\,kJ/mol$) to force myosin head detachment during cross-bridge cycling.

Calorimetry

The measurement of heat energy released during metabolism or food oxidation, calculated as: $\text{Heat Released (cal)} = \text{Mass of Water (g)} \times \text{Temperature Rise } (^\circ\text{C})$.

Basal Metabolic Rate (BMR)

The baseline daily energy expenditure required to sustain basic biological life at complete rest ($1,600\text{--}1,800\,kcal/day$ for adult males; $1,200\text{--}1,400\,kcal/day$ for adult females).

Revolutions Per Minute (RPM) Model

A bioenergetics model equating $1\text{ ATP Hydrolysis} = 1\text{ Cross-Bridge Cycle} = 1\text{ RPM}$, establishing that exercise intensity ($y$) increases linearly with cross-bridge rate ($x$) via $y = kx$.

Glycogen

A highly branched storage polymer of glucose stored in skeletal muscle ($\sim 400\text{--}800\,g$, local use only) and the liver ($\sim 80\text{--}100\,g$, systemic blood glucose supply).

Glycaemic Index (GI)

A numerical scale ($0\text{--}100$) measuring how rapidly and to what extent a carbohydrate food raises blood glucose levels compared to pure glucose ($GI = 100$).

Carbohydrate Loading (Carbo-Loading)

A dietary strategy for endurance events ($>90\text{ minutes}$) involving $7\text{--}12\,g/kg/day$ of carbohydrates to maximize glycogen storage, accompanied by water retention ($1\,g$ glycogen binds $\sim 3\,g\,H_2O$).

Reactive Hypoglycaemia

A sudden drop in blood glucose accompanied by shakiness, tachycardia, brain fog, and an energy crash caused by ingesting High GI carbohydrates $30\text{ minutes}$ prior to exercise.