Principles of Organisation and Human Biology

These flashcards cover the principles of biological organisation, digestive enzymes, food tests, circulatory system components, and coronary heart disease, as presented in the lecture transcript.

Cells

The basic building blocks of all living organisms.

Tissue

A group of cells that have a similar structure and perform a particular function.

Organs

Aggregations of tissues performing specific functions.

Muscular tissue

Tissue that contracts to produce movement, such as churning food in the stomach.

Glandular tissue

Tissue that secretes chemicals such as enzymes and hormones.

Epithelial tissue

Tissue that covers certain parts of the body for protection, such as the inside and outside of the stomach.

Iodine Solution

A chemical used to test for the presence of starch; it changes from browny-orange to blue-black if starch is present.

Benedict's solution

A chemical used to test for sugars; the colour change (green, yellow, or brick-red) indicates the extent of sugar present after heating in a $75\,^{\circ}\text{C}$ water bath.

Enzyme

Large proteins that act as biological catalysts, speeding up the rate of reaction without being used up.

Biuret test

A test for the presence of proteins where the solution colour changes from blue to pink/purple if protein is present.

Sudan III stain solution

A solution used to test for lipids; it form a bright red top layer if lipids are present in a sample.

Active site

A region on an enzyme with a unique shape that fits specifically onto a substrate to catalyse a reaction.

Induced fit

A model of enzyme action where the active site needs to slightly change shape in order to bind with the substrate.

Optimal conditions

The specific temperature and pH at which an enzyme works best and has the fastest rate of reaction.

Denatured

When high temperatures or extreme pH break the bonds holding an enzyme together, deforming the active site so it no longer fits the substrate.

Amylase

An enzyme produced in the salivary glands, pancreas, and small intestine that breaks down starch into maltose.

Protease

An enzyme (known as pepsin in the stomach) that breaks down proteins into amino acids; produced in the stomach, pancreas, and small intestine.

Lipase

An enzyme produced in the pancreas and small intestine that breaks down lipids (fats) into glycerol and fatty acids.

Bile

An alkaline substance produced in the liver and stored in the gall bladder that emulsifies fats and neutralises stomach acid.

Pepsin

The specific name for the protease enzyme found in the stomach, which works optimally in acidic conditions.

Amylase Reaction Rate Formula

$$\text{Rate} = \frac{1000}{\text{time}}$$

Right Ventricle

The chamber of the heart that pumps deoxygenated blood to the lungs.

Left Ventricle

The chamber of the heart that pumps oxygenated blood all around the body; it is more muscular than the right ventricle.

Pacemaker cells

Cells situated in the right atrium that produce a small electric impulse to control the resting heart rate.

Alveoli

Millions of small air sacs in the lungs surrounded by capillaries where gas exchange (oxygen and $CO_2$) takes place.

Artery

A blood vessel with thick muscular walls and elastic fibres that carries blood from the heart at high pressures.

Capillary

A tiny blood vessel with permeable walls one cell thick, used for the exchange of substances between blood and cells.

Vein

A blood vessel with a large lumen and valves used to carry blood back to the heart at low pressures.

Rate of Blood Flow Formula

$$\text{Rate of blood flow} = \frac{\text{Volume of blood}}{\text{number of minutes}}$$

Red blood cell

A biconcave-shaped cell containing haemoglobin and no nucleus, adapted to carry oxygen from the lungs to body cells.

Haemoglobin

A red pigment in blood cells that binds with oxygen in the lungs to become oxyhaemoglobin.

Phagocytosis

The process by which some white blood cells change shape to engulf bad microorganisms.

Platelet

Small fragments of cells without a nucleus that help blood clot at wounds to prevent blood loss and infection.

Plasma

A pale coloured liquid that carries blood cells, nutrients (glucose/amino acids), $CO_2$, urea, hormones, and proteins.

Coronary heart disease

A condition where coronary arteries are narrowed by fatty material build-up, restricting blood and oxygen flow to the heart.

Stents

Tubes inserted inside coronary arteries to keep them open and prevent heart attacks.

Thrombosis

The risk of a patient developing a blood clot near a stent.