Unit 1: Introduction to Biology and Biological Tools

Vocabulary practice flashcards covering fundamental concepts in biology, the scientific method, laboratory and field equipment, and the structure and function of the light microscope.

Biology

The scientific study of life or living things, derived from the Greek words bios (meaning life) and logos (meaning study).

Homeostasis

The ability of living organisms to maintain relatively constant internal conditions.

Scientific Method

A series of inquiry steps that guide scientific investigations, involving asking questions, proposing hypotheses, testing through experimentation, drawing conclusions, and communicating results.

Hypothesis

A proposed scientific explanation or possible answer for a set of questions that must be testable through experimentation.

Magnification

The number of times larger an image is compared to the actual real size of the object.

Resolution

The ability of a microscope to distinguish between two separate points.

Hand lens

A magnification tool consisting of a convex lens fixed within a circular metallic loop attached to a handle, used to enlarge the image of an object.

Compound light microscope

A microscope that uses a beam of light and two or more glass lens systems to magnify specimens up to $2000\times$, with a resolving power of $200\,\text{nm}$.

Electron microscope

A microscope that utilizes a beam of electrons and electromagnetic lenses to achieve up to $2,000,000\times$ magnification and a resolving power of $0.3\,\text{nm}$, typically used to observe dead specimens under a vacuum.

Cover slips

Small, square- or circle-shaped thin glass sheets placed over specimens on a microscope slide to lock in moisture, protect from chemicals and dirt, and safeguard the microscope.

Autoclave

Equipment used to sterilize biological samples, culture media, and bacterial spores by exposing them to high temperatures and highly pressurized steam.

Culturing

The laboratory procedure used to grow microorganisms in a controlled environment for medicine, food and beverage preparation, or biofuel production.

Incubator

A device used to maintain a specific environment and the optimal temperature suited for the growth of culturing microorganisms.

Petri dishes

Flat, shallow glass or plastic dishes with a matching cover of slightly larger diameter, commonly used with gelling culturing media such as agar.

Culture tubes

Glass tubes used to grow microorganisms with solid (gel) or liquid (broth) culturing media.

Flasks

Laboratory apparatus designed to allow easy mixing and gentle heating of liquids without spilling, functioning as large-volume culture vessels with broth media to yield large microbial populations.

Balance

A laboratory instrument used for accurately weighing specimens and making up chemical solutions.

Dropper

A laboratory tool consisting of a glass tube with a small opening at one end and a vacuum rubber bulb at the other, used to precisely control the addition of liquid solutions to reactions.

Tongs

Metallic scissor-shaped laboratory instruments used for lifting or picking up hot objects safely.

Dissecting pan

A tray or pan in which a specimen is placed and pinned down during dissection to examine its internal organs.

Crucible

A small container made of ceramic or metal designed to withstand high temperatures, commonly used for melting elements.

Beaker

A cylindrical glass container used for preparing solutions, holding hot or cold liquids, or creating ice baths.

Hotplate

An electrical apparatus used in the laboratory to heat solutions and prepare agar culturing media.

pH meter

An electronic instrument used to measure the pH (acidity or basicity) of biological and chemical solutions.

Forceps

A handheld instrument available in different shapes and sizes, used to grip, hold, or pick up small objects.

Spatula

A spoon-shaped laboratory tool used for stirring, mixing substances into solutions, and scraping materials.

Wash bottles

Flexible squeeze bottles used to rinse laboratory apparatus, allowing the user to adjust water pressure by squeezing.

Bunsen burner

An apparatus that produces a single open flame, used for heating and sterilization procedures during laboratory experiments.

Insect nets

Field collecting gear comprising a cloth or fine mesh net bag affixed to a wire loop on a wooden or metal pole, used to catch insects.

Fishing net

A grid-like mesh device made from woven fibers or tied thin thread used for catching fish or serving as a fish trap.

Quadrat

A small frame used in ecological field research to conduct population and distribution studies.

Total magnification

The overall enlargement of an image in a compound light microscope, calculated as the product of the eyepiece power and the objective lens power (e.g., $10\times \times 40\times = 400\times$).

Eyepiece (Ocular)

The top optical lens of the microscope through which the user looks, having a standard magnification of $10\times$ (optional lenses ranging from $5\times$ to $30\times$).

Objective lenses

The primary magnification lenses located on the revolving nosepiece, typically providing powers from $4\times$ to $100\times$.

Nosepiece

The movable, circular rotating mount that holds multiple objective lenses, enabling the user to switch magnifying powers.

Coarse adjustment knob

The adjustment knob that moves the stage noticeably to roughly establish focal distance and bring the specimen into general focus.

Fine adjustment knob

The adjustment knob that moves the stage minimally to regulate distance precisely and achieve sharp image focus.

Microscope stage

The flat platform upon which the microscope slide holding the specimen is placed for viewing.

Aperture

The opening located in the center of the microscope stage through which light from the illuminator reaches the specimen.

Condenser

A lens system beneath the stage adjacent to the diaphragm that concentrates and focuses light from the illuminator onto the specimen, essential for magnifications of $400\times$ and higher.

Diaphragm (Iris)

An adjustable apparatus beneath the stage that regulates the amount, size, and intensity of the light beam reaching the specimen.

Microscope base

The bottom foundation that supports all mechanical and optical components of the microscope and houses the light source.