Measurement and Lab Equipment Basics Unit 1 Lesson 1

Measurement and Lab Equipment Basics Students will be able to: Explain units of metric systems. Know the conversion within the metric systems. Know different types of equipments in a biology laboratory. Explain the importance of glasswares and instruments used. Key Vocabulary: Fundamental units, units of metric systems, glasswares, beaker, conical flask, graduated cylinder, Bunsen burner, spirit lamp, pH meter, digital balance, compound microscope.

Measurement and Lab Equipment Basics Any object has its own shape, size and dimension. In biology, it is very important to know the overall physical and chemical status of any living organism. There are specific units to describe various characteristic features that come with proper symbols. Green plants can make their own food

Measurement and Lab Equipment Basics Fundamental Units: these units are the units of fundamental quantities. The fundamental units are followed throughout the world. Whereas USA has its own U.S. Customary units for almost all physical quantities. Physical Quantity Units in Metric System Symbol U.S. Customary Units Mass Kilogram Kg Pound lb Length Meter M Feet ft Time Second S Temperature Centigrade C Fahrenheit F Volume Liter L Gallon gal

Measurement and Lab Equipment Basics Unit of length Length is generally measured in meters. In Metric system, units of length are micrometers (µm), millimeters (mm), centimeters (cm), meters (m) and kilometers (km). Feet and inch are also units of length in U.S. Customary Units.

Measurement and Lab Equipment Basics 1 meter = 100 centimeters 1 centimeter = 0.01 meter 1 meter = 1,000 millimeters 1 kilometer = 1,000 meters 1 inch (in) = 2.54 centimeters 1 feet = 12 inches 1 feet = 0.3048 meter

Measurement and Lab Equipment Basics Size of Various Molecules and Cells

Relationships between organisms Units of Mass in Metric System: The mass is measured in grams. Like length, mass also has different units within the Metric system and these are micrograms (µg), milligrams (mg), grams (gm) and kilograms (kg). In U.S. Customary units, another unit of mass is ounce and pound. 1 kg = 2.21 pounds

Relationships between organisms Units of Volume in Metric System: Volume is generally measured in milliliter (ml). Volume also has different units within the metric system such as microliters (µl), milliliters (ml) and liters (l). 1 cc = 1 ml 1 liter = 1 dm3 1 gallon = 3.8 liters 1 ounce = 30 ml

Relationships between organisms Units of Temperature in Metric System: Temperature is generally measured in degree centigrade (°C). In U.S. Customary unit temperature is measured in degree Fahrenheit (°F). Converting Fahrenheit to Celsius: Subtract 32 from the Fahrenheit value. Multiply the obtained value by 5. Then divide the resultant by 9.

Relationships between organisms Conversion from Celsius to Fahrenheit: Multiply the temperature in (°C) by 9. Divide the obtained number by 5. At last, add 32 in it.

Relationships between organisms Conversion of Units Within Metric System: The units of length, mass, time and temperature can be converted within the metric system. Let’s take an example. You can calculate the length of any object using a scale. Here scale is acting as a tool for measuring the length of an object such as a paper. You can calculate the length of that paper in meter, centimeter, millimeter, etc or even convert it into various units of length.

Relationships between organisms If the length of a paper comes to 10 cm, it can be converted to mm. As you known that 1 cm = 0.01 m therefore, 10 cm will be equal to 10 X 0.01 m = 0.1 m. Now you have to convert 0.1 m to mm. As you know that 1 m = 0.001 mm, therefore 0.1 m will be equal to 0.1 X 0.001 mm = 0.0001 mm or 10-4 mm. A Scale

Relationships between organisms Measuring Cylinder It is also known as graduated cylinder and used to measure the volume of a liquid in ml. The measuring cylinder has marking on it so that the correct amount of liquid can be measured with it. While measuring any liquid two meniscuses are observed, lower meniscus and upper meniscus due to surface tension. It should be noted that during measuring a liquid, the lower meniscus is considered, and the reading is noted.

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Relationships between organisms Beaker It is used to store the measured amount of liquid in it. It is also used to hold solids and to mix materials. It comes in various capacity such as 50 ml, 250 ml, 500 ml, 1000 ml, etc.

Relationships between organisms Erlenmeyer Flask This is also known as conical flask due to its conical shape. Like a beaker, the flask is also used to hold certain amount of solids or liquids. It is generally used to heat any liquid and solid and also stirring as it can avoid spilling due to its shape.

Relationships between organisms Bunsen Burner It is used for burning or heating things such as liquids and solids. It is commonly used in biology and chemistry laboratory. Spirit Lamp It is also used for the same purpose as the Bunsen burner. It has a container filled with spirit or alcohol and a wick inside.

Relationships between organisms Burette It is used to measure very accurate amount of liquid. It is also used in titration process to hold certain amount of dye in it. It is basically used in biological and chemical experiments.

Relationships between organisms Dropper It is used to transfer one drop of liquid at a time. It can be made up of plastic or glass. The disposable droppers are made up of plastic.

Relationships between organisms Pipette It is also used to get the accurate amount of liquid in very small amount that cannot be measured by a graduated cylinder. It can measure volume of liquid in millimeters also. There are two types of pipettes- glass pipette and micropipette. A glass pipette is most commonly used in the laboratory whereas a micropipette is used in research studies for measuring minute amount of liquid. The glass pipette is also known as graduated pipette.

Relationships between organisms Pipette It is also used to get the accurate amount of liquid in very small amount that cannot be measured by a graduated cylinder. It can measure volume of liquid in millimeters also. There are two types of pipettes- glass pipette and micropipette. A glass pipette is most commonly used in the laboratory whereas a micropipette is used in research studies for measuring minute amount of liquid. The glass pipette is also known as graduated pipette.

Relationships between organisms Graduated Pipette Micropipettes

Relationships between organisms Wire Gauge It is a mesh like structure made up of iron that is used to hold a beaker or a flask while heating. It is square in shape with a round asbestos sheet in the center of the square.

Relationships between organisms Test tube It is the most common glassware used in a biological laboratory. It also comes in various sizes. It is used to mix liquids, solids with liquid, heat the chemical, grow cultures, etc.

Relationships between organisms Test Tube Rack This is like a stand that is used to hold 5-10 test tubes in a laboratory. Spatula It is used to pick small quantity of solid or chemical and for transferring it to any container.

Relationships between organisms Mortar Pestle It is made up of porcelain and used to crush and grind solids into fine powder or mixture. Watch Glass It is a small glassware used to hold small amount of solid and liquid chemicals. It can also be used as a cover for a beaker.

Relationships between organisms Petri Dish A petri dish is a shallow glass or plastic dish that comes with a cover. It is named after its inventor Julius Richard Petri. It is used by the biologists to grow microbiological cultures.

Relationships between organisms Digital Balance It is also known as analytical balance. It is used to measure the weight of any solid. The chemical to be weighed is not directly placed on the weighing pan. After switching on the machine, the weighing boat or a white paper is kept on the weighing pan and then “tare” button is pressed.

Relationships between organisms This makes the reading again to “zero”. Then, the chemical to be weighed is kept on the paper or weighing boat. The reading that comes on the scale is the weight of that chemical.

Relationships between organisms pH Meter A pH meter is an instrument most commonly used in a science laboratory to determine the acidity and alkalinity of a sample liquid. It measures the hydrogen ion concentration in the given solution. A solution that has more hydrogen ion concentration is more acidic while those having more hydroxyl ion concentration is more alkaline. pH is measured on a scale from 1 -14. 7 is considered as neutral, below 7 is acidic and above 7 is alkaline.

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Relationships between organisms A pH meter consists of a glass probe that has two glass electrodes- a sensor electrode and a reference electrode. The sensor electrode is made up of permeable glass membrane which is coated with silica and metal salts. It also contains a silver chloride coated wire immersed in the pH buffer solution. The reference electrode consists of potassium chloride solution in which a wire coated with silver chloride is immersed.

Relationships between organisms When the glass pH probe is placed in the sample solution, the hydrogen ions accumulate around the bulb that replaces the metal ions. This exchange of ions leads to electric flow which is measured in the form of pH of that solution. Relationships between organisms

Relationships between organisms pH Meter A pH meter is an instrument most commonly used in a science laboratory to determine the acidity and alkalinity of a sample liquid. It measures the hydrogen ion concentration in the given solution. A solution that has more hydrogen ion concentration is more acidic while those having more hydroxyl ion concentration is more alkaline. pH is measured on a scale from 1 -14. 7 is considered as neutral, below 7 is acidic and above 7 is alkaline.

Relationships between organisms pH Meter A pH meter is an instrument most commonly used in a science laboratory to determine the acidity and alkalinity of a sample liquid. It measures the hydrogen ion concentration in the given solution. A solution that has more hydrogen ion concentration is more acidic while those having more hydroxyl ion concentration is more alkaline. pH is measured on a scale from 1 -14. 7 is considered as neutral, below 7 is acidic and above 7 is alkaline.

Relationships between organisms Compound Microscope A compound microscope is also known as student microscope that is most commonly used in a biology laboratory. It uses two lenses – one close to the object and one close to the observer’s eye. Eye piece lens is close to the observer’s eye while the objective lens is close to the object to be observed. Monocular microscope has a single tube with a single eyepiece while a binocular microscope has two tubes each with one eye piece.

Relationships between organisms Compound Microscope

Relationships between organisms Summary It is important to know the fundamental units and their conversions within the metric systems. Length is measured in meter, mass in grams, volume in milliliters and temperature in degree centigrade. Glasswares and equipments are widely used in laboratories such as measuring cylinder, beaker, flask, pipette, test tube, pH meter, digital balance, compound microscope, etc.