Microscopes, Bacteria & Lab

Bacteria that stains pink with Gram stain are said to be…

Gram Negative

Bacteria that’s stains purple with Gram stain are said to be…

Gran Positive

An organisms that require oxygen for metabolism and survival

Aerobe

An organism that do not require oxygen for metabolism and survival

Anaerobe

An organism that directly gets energy from the sun

Phototroph

An organism that gets its energy by breaking bonds

Chemotroph

An organism that directly produces its own food and energy

Autotroph

An organism that gets its food and energy from eating other living things

Heterotroph

The lens on the microscope closest to the eye

Ocular Lens

The lens on the microscope closest to the object

Objective Lens

Is used because it has the same refractive index as glass and it reduces the refraction

Oil Immersion

The bending of light as it passes through different substances

Refraction

The ability to distinguish two points as being separate

Resolution

Making something appear larger

Magnification

A single rod-shaped bacteria

Bacillus

A single spherical shaped bacteria

Coccus

A single spiral shaped bacteria

Spirillum

You should never use oil with non-oil objective because it might _______ into the housing

Leak

You should always work at these to prevent contaminating your samples

Angles

You should always use these techniques to prevent yourself and bacteria from becoming contaminated

Sterile

Things that cause disease or illness are called…

Pathogens

What is FOV?

The diameter of the circle of light that can be viewed with an ocular Lense

What is Fits?

How many bacteria can fit across the FOV

D.) 4

B.) 10x

D.) 100x

A.) low power lens

C.) start with coarse focus and then use the fine focus for each objective

B.) the diameter of the circle of light that can be viewed with a given objective lens

C.) use oil

D.) reduce refraction and improve resolution

B.) lens paper using a dabbing motion

D.) all of the above

A.)

Low: 4.0mm

Medium: 1.8mm

High: 0.4mm

Oil: 0.25mm or 250μm

C.) AS = FOV/FITS

A.) I and III, only

B.) phototrophs

C.) anaerobes

B.) heterotrophs

C.) gram positive, diplococci

B.) capsule

B.) pili

C.) bacteria that have mutated such that they can no longer be killed by an antibiotic

C.) a zone of inhibition around the disc

D.) I, II, and III, only

What is negative control?

A group in an experiment that gets no treatment and is expected to show no effect, helping confirm that the results are valid.

What is the order of all the metric prefixes?

Mega: M

—

—

Kilo: k

Hecta: h

Deca: da

Base: g, mol, L, m

Deci: d

Centi: c

Milli: m

—

—

Micro: μ

What is the magnification of low, medium, high, and the oil and the ocular objective lens?

4x, 10x, 40x, 100x, and 10x

What is the FOVS’ for all objective lenses

4.0mm, 1.8mm, 0.4mm, and 0.25mm or 250μm

What is the difference between resolution and magnification?

Resolution is the ability to distinguish two points as being separate while magnification is making something appear larger.

Why do we use oil immersion?

We use oil immersion because the oil has a similar refractive index to glass, which reduces light refraction and allows more light into the lens. This increases resolution and gives a sharper, clearer image.

What are some do’s and don’ts’ of biological drawing?

• no shading

• Don’t use colour; describe colour

• Large, clear; ½ of a page

• Drawing should be on left

• Identify structure

• Right, form a vertical list

• Words horizontal

• Draw lines using a ruler

What does prokaryote and unicellular mean?

Prokaryotes are before nucleus or no nucleus, and is unicellular because it only made of one cell.

What are some basic structure of a bacteria?

What can be seen and can’t be seen under the microscope?

Seen:

• cell

• Bacteria

Can’t see:

• viruses

• Ribosomes

• Molecules

• Anything mitochondria size or smaller

What is sterile technique?

Sterile technique means preventing contamination by keeping tools clean, avoiding contact with non-sterile surfaces. This includes quickly opening plates, using sterile Q-tips or loops, flame-sterilizing equipment, and keeping your workspace and hands clean to ensure only the intended bacteria are collected and handled.

What’s is positive control and negative control?

A positive control is a part of an experiment that is expected to show a known, proving the setup works. A negative control is expected to show no reaction or change, proving that any observed effect in the experiment is due to the variable being tested and not something else.