Grade 10 biology – Transport Quiz

Blood is the primary transport medium in most animals, carrying oxygen, nutrients, hormones and wastes between organs and tissues.

Haemoglobin is the iron-containing pigment in red blood cells that binds and transports oxygen from the lungs or gills to tissues.

Mature mammalian red blood cells lose their nucleus to provide more space for haemoglobin, improving oxygen-carrying capacity.

Platelets aggregate at wound sites and help form a clot, preventing blood loss and allowing repair.

ABO blood groups are determined by the presence or absence of A and B carbohydrate antigens on red blood cell membranes.

Double circulation means there are two separate circuits: the pulmonary circuit to the lungs and the systemic circuit to the body, with blood passing through the heart between them for efficient oxygenation.

Fish have single circulation: blood flows from heart to gills to the body and back to the heart, passing through the heart only once each circuit.

Frogs have a three-chambered heart (two atria, one ventricle) so some mixing of oxygenated and deoxygenated blood occurs in the ventricle, making circulation incomplete.

Atrioventricular valves sit between atria and ventricles and close when ventricles contract, preventing blood from flowing back into the atria.

Semilunar valves are located at the bases of the aorta and pulmonary artery and prevent backflow into the ventricles after contraction.

Capillaries have thin walls that allow materials to pass between blood and surrounding cells, enabling exchange of gases, nutrients and wastes.

Veins often contain valves that help return blood to the heart against gravity, especially in the limbs; arteries have thicker muscular walls and carry blood away under higher pressure.

Systole is the phase when the heart muscles contract to pump blood out of the chambers; diastole is the relaxation phase when chambers fill.

The SA node in the right atrium generates electrical impulses that set the rate and rhythm of heartbeats, making it the natural pacemaker.

The lymphatic system collects excess tissue fluid (lymph) and returns it to the blood circulation; it also transports absorbed fats from the gut.

Plasma is the liquid part of blood that carries dissolved substances (glucose, amino acids, hormones, urea) and helps maintain blood volume and pH.

CO2 reacts with water in red blood cells to form bicarbonate ions, which are carried in plasma; a small amount is bound to haemoglobin or dissolved.

Blood is filtered under pressure through capillaries of the glomerulus into Bowman's capsule, forming the initial filtrate that enters the nephron.

Freshwater fish gain water by osmosis, so they produce dilute urine to remove excess water and actively transport salts in at the gills to maintain ionic balance.

Haemoglobin can bind oxygen in the lungs and release it in tissues, enabling blood to carry far more oxygen than plasma alone could.

Cardiac output equals the amount of blood the heart pumps each minute and is calculated as stroke volume (mL per beat) times heart rate (beats per minute).

During clotting, soluble fibrinogen is converted into insoluble fibrin threads that form a mesh trapping blood cells and stabilising the clot.

At high altitude oxygen levels are lower, stimulating increased erythropoiesis (red blood cell production) so blood can carry more oxygen.

Insects have hemolymph circulating in an open system; oxygen delivery is mainly via tracheae and not by the circulatory fluid.

Blood pressure at the arterial end of capillaries pushes plasma out into the surrounding tissue forming tissue fluid; some returns at the venous end or into lymph.