Page 95 - Zoo Animal Learning and Training

Chapter 5 Anatomy and Physiology 79

Epaxial
Gluteal muscles Trapezius

Fascia Latissimus
Semitendinosus dorsi Deltoid Biceps

Biceps
femoris

Triceps
Gastrocnemius

FIGURE 5.9 Muscles of a dog. Adapted from Wikimedia Commons.

Nuchal ligament
Gluteals
Splenius
Fascia
Trapezius
Latissimus dorsi External Biceps Semitendinosus
intercostals
Brachiocephalicus
femoris
Triceps Fascia

Extensor
carpus

FIGURE 5.10 Muscles of a horse. Adapted from Wikimedia Commons.

built to handle many cars, have few stop signs, and are the main From the exterior you can see the two upper chambers
means of transporting vital supplies downtown. The veins called the atria (singular, atrium), and lower chambers
handle lighter traffic and have multiple stop signs throughout called ventricles. There are four major vessels attached
the city, but eventually you can make your way back downtown. to the chambers of the heart. Two of them bring blood
These streets and roadways are connected by ramps (capillaries) to the heart: the superior vena cava and the pulmonary
that allow one car to enter or exit at a time. veins. Two allow blood to leave the heart: the aorta and
pulmonary artery.
The heart is a hollow, four‐chambered muscular All four chambers have valves that control the
organ that is divided into right and left sides (Figure 5.11). direction of the blood flow as the heart beats (Figure 5.12).