Biology - Gr.11 🦁 (UNIT 2: DIVERSITY) - Microscope & Biodiversity

— Mrcroscope —

divider

Ocular lenses (eyepiece)

part you look through to view the object

Body tube

contains the eyepiece and supports the objective lenses

Revolving nosepiece

holds the objective lenses and rotates, allowing the obj. lenses to change

Arm

connects the base to the head

Objective lenses

3 magnifications:
- low power (4x)
- med power (10x)
- high power (40x)

Stage

supports the microscope slide and has a central opening that allows light to pass through the slide

Clips

hold the stage down

Diaphragm

controls the amount of light that reaches the object being viewed

Coarse adjustment knob

moves the body tube up or down, used with low-power obj. lenses only

Fine adjustment knob

brings the object into focus

Light source

projects light upwards through the diaphragm to allow you to see the specimen

Base

support of the entire structure

Rules/Handling:

1. Microscope should be carried holding the ARM and supporting the BASE

2. Lenses should be cleaned with LENS PAPER

3. When you place the coverslip on the slide, try to avoid the formation of AIR BUBBLES

4. There are 3 objectives: 4x, 10x, 40x

5. Always start using the magnification at LOW and using the 4x objective

6. Be sure to CENTER and FOCUS the sepcimen before changing the obj. to a higher power

7. When suing the high-power lens, always focus with the FINE-ADJUSTMENT knob screw

8. To avoid damage to the microscope, store it with the LOW power obj. in place

— Biological drawings —

divider

Rules/Labs:

1. Always use a BLANK sheet of paper & PENCIL

2. Always use a compass or petri dish for a PEREECT CIRCLE

3. Avoid COLOURING or SHADING/HATCHING. Use the stippling method.

4. Place labels on the LEFT and use a RULER for creating lines

Depth field:

the depth of the object that is in focus at any one time

Eyepiece ALWAYS has a magnification of __

10x

Field of view:

visible portion of a specimen viewed through the eyepiece of an optical microscope

The eyepiece has 3 possible magnifications:

4x, 10x, 100x

Total magnification:

ocular magnification x magnification of th lens you are using

As magnification increases, the field of view ___

decreases

Fit number:

estimate of number of the number of times (in length) the specimen you are observing can be placed withtin the diameter of the field of view

Actual size:

the real proportions of a biological drawing in real life

Scaled ratio:

divide length of the cell or structure (in mm) by the actual size (in mm)

Rules:

• MUST appear NEXT to the title of your drawing and in SAME units

— Conversions & formulas —

divider

mm (milimeter) → um (micrometer)

x1000

ACTUAL SIZE (A.S) =

Field of view diameter / “Fit Number”

SCALED RATIO (S.R) =

Length of the cell or structure drawing (mm) /Actual size (A.S) of the cell or structure (mm)

Biodiversity:

the natural diveristy or variation of living organisms

Sustainable development:

development that meets the needs of the present w/o compromising the ability of future generations to meet their own needs

THREE main levels of biodiversity:

• Specific diversity (species)

• Genetic diveristy (DNA)

• Ecosystem diveristy

1. Specfic diversity (species):

The variety tat exists in the different species found in a give n area

2. Genetic diversity (DNA):

The variety that exists at the level of alleles, that of entire genes or that of chromosomal structure withtin species

3. Ecosystem diversity

The variety that exists in physical environments and biotic communities in a landscape (ecosystem)

Anthropocene

A term that describes a geological period during which humans caused the majority of planetary changes

Ecoservices:

the benefits that sustainable ecosystems provide to the organisms that live in them, including humans, which are linked to diversity

Ensure maintenance, organisms contribute to:

• Pest control

• Pollination

• Waste management

• Recycling nutrients

• Climate regulation, etc.

Geological period:

a period where umans caused the majority of planetary changes

What are TWO things that humans have modified?

Climate & biodiversity

Macroevolution:

large-scale evolution can lead to the appearance of new species

WHAT ARE THE 3 DOMAINS OF LIFE:

• Eubacteria (bacteria)

• Archaea

• Eukarya (Eukaryotes)

Phylogeny

the history of the evolution of a species and their relationships

Who is the Father taxonomy?

Carl Linnaeus

Taxonomy:

branch of biology which aims to identify, name and classify species according to their natural characteristics

Taxa:

a group that refers to organisms such as the phylum chordates or other rodents

What is the largest Taxa?

The Domain

How are animals are classified?

D(Domain) ead

K(Kingdom)ings

P(Phylum)lay

C(Class)hess

O(Order)n

F(Family)at

G(Genus)reen

S(Species)tools

Binomial nomenclature

a system of naming plants & animals in which each species is given a name consisting of two terms → First name: genus → Second name: species

1. First word refers to:

Genus

2. Second refers to:

Species

What is a dichotomous key?

an identification tool which consists of a series of binary choices which guide towards the identification of organims

What are prokaryotes?

a unicellular organism w/o a nucleus & membrane-bound organelles

What’s an example of prokaryotic cell?

a bacteria

What are the FOUR important BACTERIUM?

• Proteobacteria

• Cyanobacteria

• Gram-Positive bacteria

• Gram-Negative bacteria

FUN FACT ABOUT BACTERIA!

→ They have cell walls !

When grain-staining, the dye binds to the walls, which thickens to create a PINK or PURPLE colour

Proteobacteria:

ancestors of the mitochondria

Cyanobacteria:

ancestors of chloroplasts

Gram-Positive bacteria:

their walls have a thick layer of petidoglycan

→ Turns purple

Gram-Negative bacteria:

their cell walls have a thin layer of peptidoglycan

→ Turns pink

Bacteria can either be ____ or ___

useful or harmful

Examples of Archaea:

• Methanogens

• Halophiles

• Extreme thermophiles

• Psychrophiles

• Acidophiles

Methanogens:

produce methane uder hypoxic conditions

Halophiles:

survive in high salt

Extreme thermophiles:

survive in high temps

Psychrophiles:

survive in low temps

Acidophiles:

survive in an acidified environment - ph <3.0