Frog Dissection - PowerPoint Presentation

Slide1

Frog Dissection

Biology Slide2

What is the purpose of dissections?

What can we learn from any dissections? Slide3

Our purpose for dissection:

To dissect a frog in order to: Understand the external and internal anatomy of a frog

Compare this to structures of the human anatomy Contrast homologous structures and explain why they are different in a frog or in a human Slide4

Rules of Dissection

In a dissection any “horsing around” will result in an automatic Category 2 (a Saturday)If you receive a Category 2 and are still horsing around you are now putting other peoples safety on the line and will not be allowed to dissect or allowed into the classroom (this means sitting with the deans for the remainder of dissections)---This will result in a zero for your dissection packet

What does it mean to be horsing around? Slide5

If you are absent

You must come before or after school to make up your missing work Slide6

Lab Safety Rules

1

) Always follow all instructions given by your teacher.2) Always wear all safety equipment-this includes safety goggles.3) Use dissection equipment only for its intended purpose. ( NO playing around will be allowed!)

4) Be careful! Watch carefully when you are walking around, and do not leave your lab station if you don

’

t have to.

5) Do not carry dissection equipment (like pins, scissors, scalpels) around the room

.

6) Ask your group and read through procedure BEFORE you ask me

7) If someone is hurt you tell a teacher IMMEDIATELLY Slide7

Clean Up Procedures

At the end of each day:

-Place the frog in a ziploc bag with your group member’

s names on it.

-Wash all dissecting equipment and return it to the front of the room.

-Wash the

dissection pan

and dry it and return it to the front of the room.

-Clean your lab area and make sure the table is clean and dry.

-Return your safety

goggles.Slide8

Schedule

Part 1:

External Anatomy, Muscles, and the Oral CavityPart 2:

Internal Anatomy (Digestive, Circulatory and Reproductive systems)

Part 3:

Internal Anatomy (Nervous System) and ConclusionSlide9

Tools used in dissection

Dissection Pans

– all dissection takes place in the pan, bottom is made of wax

Dissection Pins

– used to pin down appendages and flaps of skin and muscle

Dissection Probes

– used to hold, move, or manipulate while dissectingSlide10

Scissors

– used to cut through skin, muscle, and bone

Forceps – used to pick up small parts and move materialSlide11

Scalpels

These are used to cut through skin, bone, and muscle

This is how to correctly hold a scalpel

In which direction should you ALWAYS cut using a scalpel?

ALWAYS CUT TOWARDS YOUR OWN BODY

Should you ever feel a scalpel bending?

What should you do if you do?

NO

IF YOU DO, STOP CUTTING AND TRY A NEW WAYSlide12

Dissection Terminology

Dorsal: back side

Ventral: front sideAnterior: towards the head end

Posterior: towards the tail endSlide13

Basic Frog Information

Frogs are members of the class called

Amphibia

Commonly, we call them

“

Amphibians

”

.

Amphibians

are cold blooded vertebrates. They do not have scales, and they live mostly on land but return to water to breed.Slide14

Frogs need to live near water because:

They absorb most of of the moisture they need through their

skin

.

They lay their eggs in water, and baby frogs (tadpoles) spend the beginning of their lives in waterSlide15

A typical frog meal includes bugs, worm, insects, and snails. Frogs don

’t chew – they swallow their meals whole!