Wacky Wednesday!

Agenda:

• Take out UP 11-17 w/ stampsheet
• Discuss the heart
• Work on colorcodes 

 The first thing that we did today was fill out a diagram of the heart. We then discussed the different parts of the heart that were shown on the diagram.

Circulation in Humans

The heart has 4 chambers and has a double-loop circulation system.

• Pulmonary circulation: blood is pumped from the right side of the heart to the lungs
• Systematic circulation: blood is pumped from the left side of the heart to the rest of the body

The Human Heart

The heart is a hollow muscular organ surrounded by a protective sac called the pericardium. Myocardium is the muscle in the heart walls. The septum divides the heart in half so that deoxygenated blood doesn't mix with the oxygenated blood. The 2 chambers at the top of the heart are the atrium and the 2 on the bottom are the ventricles. Valves separate the atrium from the ventricles so that the blood wont flow backwards.

Blood Vessels 

Arteries: 

• carry blood away from the heart
• are thicker to accommodate pressure
• coronary arteries- bring blood from the heart back to the the heart's muscle to provide oxygen for the heart cells

Veins: 

• brings blood to the heart
• have valves

Capillaries: 

• smallest vessels; only one cell thick
• diffusion occurs between capillaries and all cells
• gas exchange

 Homework:

1. UP 21-23
2. Quiz tomorrow on: 

• heart parts
• order in which blood flows through the heart
• which side of the heart has oxygen/deoxygenated blood
• structure/functions of blood vessels