AQA GCSE Biology (Combined Science) Unit 2: Organisation

Flashcards for key concepts from AQA GCSE Biology (Combined Science) Unit 2: Organisation.

In the food tests, a positive result for starch indicates a __ color change with iodine.

Blue-black

The independent variable in the investigation of amylase is the __ of the buffer solution.

pH

Blood returning to the heart from the body enters the right atrium via the __.

vena cava

The three types of blood vessels are arteries, veins, and __.

capillaries

The heart acts as a __ pump serving two circulatory systems: pulmonary and systemic.

double

In the heart, the sino-atrial node (SAN) is responsible for initiating __.

electrical impulses

When an enzyme loses its shape and can no longer function, it is said to be __.

denatured

Xylem vessels primarily transport __ from the roots to the leaves.

water

Phloem vessels transport __ such as glucose around the plant.

food

Carcinomas are associated with __ cell growth and division, leading to tumors.

uncontrolled

Artificial pacemakers may be implanted if the heart's __ are not functioning properly.

nodes

A high-fat diet can lead to an increase in __ levels in the body, raising the risk of heart disease.

cholesterol

The __ controls the opening and closing of the stomata in leaves, regulating gas exchange.

guard cells

In the lungs, oxygen binds to __ within red blood cells to form oxyhaemoglobin.

haemoglobin

Blood flow through arteries is generally under __ pressure compared to veins.

high

The __ are structures that prevent the backward flow of blood in the heart and veins.

valves