B3.2 - Everything in the Specification

Which system transports substances around the body?

The heart is an [blank_start]organ[blank_end] and [blank_start]pumps[blank_end] [blank_start]blood[blank_end] around the body. Much of the wall of the heart is made from [blank_start]muscle[blank_end] [blank_start]tissue[blank_end].

Label the highlighted parts of the heart.

Blood enters the [blank_start]atria[blank_end] of the heart. The [blank_start]atria[blank_end] [blank_start]contract[blank_end] and force blood into the [blank_start]ventricles[blank_end]. The [blank_start]ventricles[blank_end] [blank_start]contract[blank_end] and force blood out of the heart. [blank_start]Valves[blank_end] in the heart ensure that blood flows [blank_start]in the correct direction[blank_end]. Blood flows from the heart to the organs through [blank_start]arteries[blank_end] and returns through [blank_start]veins[blank_end]. There are two separate [blank_start]circulatory[blank_end] systems - one for the [blank_start]lungs[blank_end], and one for all the other organs in the body.

What are the characteristics of arteries?

What are the characteristics of veins?

STENTS - [blank_start]Narrow[blank_end] [blank_start]tubes[blank_end] capable of supplying a [blank_start]blood[blank_end] [blank_start]flow[blank_end] equivalent to an [blank_start]artery[blank_end]

[blank_start]Coronary heart disease[blank_end] can be caused by [blank_start]fatty deposits[blank_end] building up on the inner surface of [blank_start]arteries[blank_end]. These deposits restrict blood flow and can cause [blank_start]heart attacks[blank_end]. [blank_start]Stents[blank_end] can be inserted into the [blank_start]arteries[blank_end] and can increase the blood flow to the [blank_start]heart muscles[blank_end]. Stents do have some drawbacks: they can irritate the [blank_start]artery lining[blank_end], causing [blank_start]scar tissue[blank_end] to grow there, and drugs must be taken to avoid [blank_start]blood clotting[blank_end] in the stent itself.

In the [blank_start]organs[blank_end], blood flows through very [blank_start]narrow[blank_end], [blank_start]thin-walled[blank_end] [blank_start]blood vessels[blank_end] called [blank_start]capillaries[blank_end]. [blank_start]Substances[blank_end] needed by the [blank_start]cells[blank_end] in body [blank_start]tissues[blank_end] pass out of the [blank_start]blood[blank_end], and [blank_start]substances[blank_end] produced by the cells pass into [blank_start]the blood[blank_end] through the [blank_start]walls[blank_end] of the capillaries.

Blood is a tissue.

Blood consists of plasma, red blood cells, and white blood cells.

Blood plasma transports [blank_start]carbon dioxide[blank_end] from the organs to the [blank_start]lungs[blank_end], [blank_start]soluble products of digestion[blank_end] from the [blank_start]small intestine[blank_end] to other organs, and [blank_start]urea[blank_end] from the [blank_start]liver[blank_end] to the kidneys.

a) What do white blood cells have that platelets don't? b) What do white blood cells do? c) What do platelets do?

Red blood cells transport [blank_start]oxygen[blank_end] from the lungs to the [blank_start]organs[blank_end]. Red blood cells have no [blank_start]nucleus[blank_end]. They are packed with a [blank_start]red[blank_end] pigment called [blank_start]haemoglobin[blank_end]. In the lungs, haemoglobin combines with [blank_start]oxygen[blank_end] to form [blank_start]oxyhaemoglobin[blank_end]. In other organs, [blank_start]oxyhaemoglobin[blank_end] splits up into haemoglobin and [blank_start]oxygen[blank_end].

Flowering plants have separate transport systems: - [blank_start]Xylem tissue[blank_end] transports [blank_start]water[blank_end] and [blank_start]mineral ions[blank_end] from the [blank_start]roots[blank_end] to the [blank_start]stem[blank_end] and [blank_start]leaves[blank_end]. - [blank_start]Phloem tissue[blank_end] carries [blank_start]dissolved sugars[blank_end] from [blank_start]the leaves[blank_end] to the rest of the [blank_start]plant[blank_end].

TRANSPIRATION SYSTEM - The [blank_start]movement[blank_end] of water from the [blank_start]roots[blank_end] through the [blank_start]xylem[blank_end] and out of the [blank_start]leaves[blank_end] is called the transpiration system.