Apparatus and Techniques N5 SQA

Apparatus and Techniques

​National 5 Biology

Sophies Tutoring Caithness

Beaker

A glass container with a pouring lip, used to hold, mix or heat substances

Balance

Scales used to measure mass

​Measuring cylinder

A cylindrical container used to measure the volume of liquid

​Dropper/Pipette

A thin, tapering glass or plastic tube used to eject or suck in a small amount of fluid.

Test tube

A thin, cylindrical container, usually made of glass. Used to hold chemical and biological substances

​Boiling tube

A slightly larger glass test tube. Used to heat substances over a bunsen burner.

Thermometer

A device that measures temperature

Funnel

A tube that is wide at one end and narrows at the other. Used to move liquids or particles through a narrow opening,

​Syringe

A tube and plunger used to eject or suck in a fluid or gas

​Timer/Stopwatch

Used to measure the duration of an event. Usually hand-held and operated by buttons.

Microscope

A device that uses lenses to magnify items that are normally too small for the human eye to see

Petri dish

A glass or plastic circular dish. used in combination with agar to grow cells

​Quadrat

A square grid, often 1m squared. Used to sample plants or slow moving animals

​Pittfall trap

A container embedded in the ground and protected by a flat roof covering. Used to trap small animals often for biodiversity sampling.

​Light meter

A meter that measures light intensity

Moisture meter

A meter that can be used for measuring moisture

​Water Bath

A container that keeps water heated at a fixed temperature. Used for incubating samples.

​Measuring enzyme activity

​Catalase

Measuring enzyme activity

Measuring respiration

Respiration by living organisms can be investigated by carrying out experiments to show carbon dioxide production. If carbon dioxide is bubbled through limewater, then it turns from clear to cloudy/milky in colour. This is why limewater used in a simple respirometer can show that more carbon dioxide is present in exhaled air compared to inhaled air.

​Measuring respiration

Fill in the Blanks

If inhaled air contains 0.04% carbon dioxide and exhaled air 4%, how many times more carbon dioxide do you breathe out than in?

Measuring Transpiration

A potometer can be used to measure the volume of water absorbed. Usually, a leafy shoot is used instead of a single leaf.

A single potometer comprises:

• A container of water

• A capillary tube

• Rubber tubing to connect the capillary tube to the stem of the leafy shoot

• A scale to measure the distance travelled by a bubble in the capillary tube

Measuring Transpiration

The faster the bubble moves, the greater the rate of water uptake - and so the greater the rate of transpiration. You can vary the conditions to investigate the effect of:

• Changing temperature

• Humidity

• Wind speed

• Light intensity

​Measuring transpiration

​Measuring abiotic factors

​Abiotic factors	Equipment ​	​Tips to avoid error
​Temperature	Thermometer​	Don't shade it​
​Light Intensity	Light meter​	Don't shade it. Position it facing maximum sunlight. Keep it steady.​
​Soil pH	Soil pH meter​	Make sure the probe is dry and clean before use. Keep the probe at a consistent depth.
​Soil moisture	Soil moisture meter​	​Make sure the probe is dry and clean before use. Keep the probe at a consistent depth.