LAB 1 : Toad Dissection (Integumentary and Muscular Systems)

toad

used because:

• locally abundant

• inexpensive

• easy to obtain

• large body size for easier dissection

model organism

anatomy is similar to humans and other vertebrates, used for studying structure and function

integumentary system

outer covering of the body consisting of the skin and external body features

skin

external covering of the body that functions in protection, sensation, excretion, and respiration

muscular system

system composed of skeletal muscles that allow movement of the body

skeletal muscles

voluntary muscles attached to bones

organ system

group of organs working together to perform a specific function

organ

collection of tissues joined to perform a specific function

axial region

body region composed of the head and trunk

appendicular region

body region composed of the limbs

snout

protruding triangular region of the head anterior to the eyes

external nares

the nostrils

eyes

sense organs located on the dorso-lateral portion of the head

nictitating membrane

transparent third eyelid that protects the eyes

tympanic membrane

circular thickened membrane behind each eye that serves as the eardrum

thoracic region

anterior half of the trunk containing the parotoid glands

parotoid glands

poison glands located behind the tympanum in toads

abdominal region

ventral part of the posterior trunk

lumbar region

dorsal part of the posterior trunk

upper arm

first segment of the forelimb attached to the trunk

middle forearm

segment below the upper arm

carpus

wrist

manus

hand

fingers

four digits of the forelimb

pre-pollux

rudimentary first finger felt as a short stump

thigh

first segment of the hindlimb attached to the body

shank

lower leg

tarsus

ankle

pes

foot

pre-hallux

degenerated digit considered the sixth toe

masseter

jaw muscle near the back of the head

depressor mandibularis

muscle that opens the mouth

temporal

muscle that assists in jaw movement

latissimus dorsi

broad muscle running down the back

gluteus

small muscle at the top of the hind leg

triceps femoris

thick muscle on the outer thigh

biceps femoris

large muscle on the back thigh

gracilis minor

narrow muscle along the inner thigh near the knee

chloroform

chemical used to euthanize the specimen

formalin (10%)

preservative used to store the specimen

dissecting pan with wax

platform used to pin the specimen

pins

used to secure the specimen in position

forceps

tool used for gripping tissues

dissecting scissors

tool used for cutting skin and muscles

dorsalis scapulae

shoulder

longissimus dorsi

along spine