Week 3 - Shark circulatory system

Next week, problem solving week

Bring books that might help you, if you wish (vertebrate, animal physiology, etc).

Handouts for next week will be given to you at the beginning of the lab session.

Lab exam three weeks today - sample questions posted on caucus group.

This week: circulatory system - below the heart

Injected with pink latex via caudal artery

When looking at arteries, take care to not destroy uninjected veins. Venous system not injected because of many troughlike veins, venous sinuses. Even with latex injection, veins are not always easy to see.

Make a flow chart - helps with your studying.

Most arteries are easy to find.

Start with dorsal aorta, formed by 4 pairs of efferent branchial arteries. Within the pleuroperitoneal cavity, it gives off a series of abdominal branches.

Locate each of the paired and unpaired branches from the dorsal aorta, using Figure 5.4, pages 58 - 60.

Keep function and integration of circulatory system in mind as you locate organs.

Segmental arteries: have three branches

parietal - body wall

vertebromuscular - vertebral column, spinal cord, muscle adjacent to neural arch

renal - kidney

Gastrohepatic artery - may be very small; branches into gastric and hepatic arteries

Posterior intestinal artery and gastrosplenic artery may branch off dorsal aorta as one and then divide.

Caudal artery seen in cut tail.

Divided into three groups:

1. Systemic

2. Hepatic portal

3. Renal portal

From one capillary bed to another

Ancestral condition - 2 portal systems

Injected with yellow latex

Gut -> liver

Moves blood from tail to kidney

Caudal vein (collect blood from capillary bed in tail)

Afferent veins

(move blood from renal portal veins to lateral surface of kidney) Efferent veins

( move blood from kidney to posterior cardinal vein)

Uninjected - difficult to see

All large veins enter into the sinus venosus.

Start with the sinus venosus and trace openings to common cardinal vein and hepatic vein

Hepatic veins at anterior end of liver

They drain the hepatic sinuses inside liver which collect blood from the sinusoids (too small to see).

Common cardinal is formed by union of anterior cardinal, posterior cardinal, inferior jugular and subclavian veins.