Lab #4: Comparative Anatomy Flashcards
Frontal/Coronal Plane
Splits subject into a FRONT and BACK
(one side will have mouth and one side will have back of head)
Transverse Plane
Cuts subject in half between upper body and lower body –> Think of cutting a banana into slices
(Ex: Cut you’d make if you wanted to look at the ring structure of the diaphragm)
Sagittal Plane
Cuts someone in half between their eyes
Superior and Inferior
(For biped)
Superior = Towards top of head
Inferior = Away from top of head (towards feet)
Rostral and Caudal
(For quadriped)
Rostral = Towards nose/beak
Caudal = Away from head
Anterior and Posterior
(For biped)
Anterior = Stomach side (face side)
Posterior = Back side (butt side)
(Front and back)
Ventral and Dorsal
(For quadriped)
Ventral = Stomach side
Dorsal = Back/spinal side
–> (Think of a dorsal fin on a whale, it’s along their spine)
Lateral and Medial
(Midline reference is between eyes)
Lateral = Away from midline
Medial = Towards midline
Proximal and Distal
Used in reference to the point of origin of a given component (typically limbs)
Proximal = Closer to point of origin/center of body
Distal = Away from point of origin/center of body
Ex: Hand is distal to the elbow
Ex: Stomach is proximal to the colon
(closer to the point of origin of the GI tract = esophagus)
Determine the following planes
Dissecting Needle
Slender tools with one end tapered to a sharp point
Used to separate and manipulate delicate tissues
Blunt Probe
Slender tools with one end tapered to a rounded point
–> Used for separating tissues, lifting structures, and exploration of internal anatomy (generally used for larger tissues)
gentle tools! They are good for detailed examination without causing damage
Forceps
Small tweezer-like tool
–> Used for grasping, holding, or manipulating tissues
Scissors
Cut through tissues cleanly and precisely
Cutters
Used to cut through bone and connective tissue (harder structures)
Worm / Isopod / Rat:
Gas Exchange Surface
Worm = Skin
Isopod = Pleopod Lungs
Rat = Alveoli
Worm / Isopod / Rat:
Blood Pump + vessels
Worm = Aortic Arches
Isopod = Heart
Rat = Heart
Worm / Isopod / Rat:
Circulatory System
Worm = Closed system (blood)
Isopod = Open system (haemolymph)
Rat = Closed system (blood)
Worm GI System Components
1) Mouth
2) Pharynx
3) Esophagus
4) Crop –> Stores food
5) Gizzard –> Grinds food
6) Intestine
7) Anus
Isopod GI System Components
1) Mouth (containes mandibles + millipedes)
2) Foregut (esophagus + stomach)
3) Hepatopancreas (produces digestive enzymes –> area of food digestion and absorption)
8) Hindgut (digestion/absorption + stool packaging)
9) Rectum
10) Anus
Rat GI System Components
1) Mouth
2) Esophagus
3) Stomach
4) Small intestine (+ liver and pancreas)
5) Colon
6) Rectum
7) Anus
Role of maxillipeds and mandibles in isopods
Mandibles = responsible for the chewing of food (like a jaw)
Maxillipeds = allow for proper orientation of food within mouth so that mandibles can chew it
Worm Excretory System
Consists of NEPHRIDIA (acts similar to human kidneys)
Filter waste from the coelemic fluid (Like ISF) and removes it through pores in the body
Rat Excretory System
The renal system –> Utilizes the kidneys to filter out the blood; any filtered material gets sent to the ureters and bladder for excretion
Isopod Excretory System
1) Maxillary glands = filters hemolymph; any filtered material leaves the body through the maxillary glands
2) Water Conductance System (directs all water to the pleopods to maintain moisture of the gas exchange surface)
3) Hindgut –> Packages stool for exit
Worm Circulatory System: How do the aortic arches act as a heart?
They connect the dorsal and ventral blood vessels!
Label the following external worm features:
1) Anus
2) Setae
3) Clitellum
4) Prostomium
5) Mouth
What is the prostomium?
In a worm it is a sensory organ near the mouth that allows the worm to sense its environment
–> Allows worms to “feel” their way through the soil
What is the clitellum?
Reproductive region!
Thickened glandular and non-segmented section of the body wall near the head (that secretes a viscid sac in which eggs are stored)
Which end of the worm was the first incision made during dissection?
WHY?
The posterior end!
–> End with the anus
We cut here to avoid any damage to the organs of study on the anterior end that could occur if we made an incision there
Why did we not cut directly down the center of the earthworm?
To prevent cutting the dorsal blood vessel
What are the three main body regions of isopods?
1) Cephalothorax (head)
2) Pereon (thorax)
3) Pleon (abdomen)
Characteristics of the isopod pereon
Segmented (usually around 7 segments)
For each Segment:
Ventral Side = Pair of pereopods (feet)
Dorsal Side = Tergite (exoskeleton)
What is located on the ventral side of the pleon?
The pleopods (lungs)
What is the pleotelson?
Last segment of the pleon (abdomen)
–> Has a pair uropods attached to it
Label the following:
What are the components of isopod antennae?
1) Peduncle (major portion of the antennae)
–> proximal portion of the antennae
–> Consists of multiple longer segments
2) Flagellum (end of the antennae)
–> Distal portion
–> Small end of the antennae that contains multiple small segments
