BIOS 255 Week 3 Lab-Blood Pressure/Blood Vessel Labeling

Student Name

Chamberlain University

BIOS-252: Anatomy & Physiology II with Lab

Prof. Name

Date

Cardiovascular System: Blood Vessels

Learning Objectives

Upon completing this module, you should be able to:

Identify and describe the structural layers of arteries and veins.
Differentiate between the structure and function of arteries and veins.
Explain the factors influencing arterial blood flow and blood pressure.
Define shock and recognize its clinical signs and symptoms.
Identify the major blood vessels involved in the cardiac, systemic, and pulmonary circulations.

Introduction

The cardiovascular system is responsible for the continuous circulation of blood throughout the body via three primary types of blood vessels: arteries, capillaries, and veins. Arteries and veins consist of three distinct tissue layers: the tunica intima, tunica media, and tunica externa. Capillaries, in contrast, are composed of a single layer of endothelial cells, which facilitates exchange of substances between the blood and tissues.

Blood pressure and flow within these vessels are influenced by several physiological factors, including vessel diameter, elasticity, and neural and hormonal regulation. Shock is a critical condition that arises when the circulatory system fails to maintain adequate tissue perfusion, leading to cellular and organ dysfunction.

In this study, learners will trace the pathway of blood through the pulmonary and systemic circulations, identifying key arteries and veins along the route. Interactive 3D models provided in Anatomy.TV will enhance understanding by allowing detailed exploration of vascular structures.

Assignment

Part 1: Anatomy.TV Activities

Complete the activities within the following sections:

Cardiovascular System: Blood Vessels
Blood Flow and Pressure
Circulatory Pathways
Vessels of the Trunk
Vessels of the Head and Neck
Vessels of the Limbs

Access Instructions:
Navigate to: Resources tab > Library > Library Resources-Database A-Z > Anatomy.TV > Cardiovascular System > Assigned Sections.
As you work through the activities, maintain a lab report to record observations and data for subsequent analysis.

Part 2: Blood Vessel Lab Report

1. Types of Blood Vessels

Blood Vessel	Histological Description / Special Characteristics	Function
Large arteries	Example: Aorta; thick tunica media with elastic fibers, connected to the left ventricle	Transport blood away from the heart
Medium arteries	Muscular arteries; tunica media contains more smooth muscle than elastic fibers	Carry blood from elastic arteries to smaller resistance vessels
Arterioles	Small arteries leading to capillaries; regulate blood flow into capillary networks	Control distribution of blood to tissues
Capillaries	Single layer of endothelial cells; no tunica media or externa	Site of exchange between blood and tissue cells
Medium veins	1 cm diameter, valves present to prevent backflow, thin tunica media	Return blood toward the heart
Large veins	Thick tunica externa, generally lacking valves	Drain blood from tributaries into the heart

2. Regulation of the Sinoatrial (SA) Node
When arterial pressure decreases, baroreceptors detect the change and relay the signal to the cardiovascular center in the medulla oblongata. The center responds by decreasing parasympathetic stimulation to the SA node via the vagus nerve while simultaneously increasing sympathetic stimulation through cardiac accelerator nerves. This dual response helps restore blood pressure and maintain homeostasis.

3. Signs and Symptoms of Shock
Shock is characterized by reduced tissue perfusion, leading to hypoxia. Common clinical manifestations include:

Hypotension (low blood pressure)
Increased heart rate (tachycardia)
Sweating and pallor
Thirst and dehydration
Confusion or altered mental status
Reduced urine output
In severe cases, metabolic acidosis such as lactic acidosis

4. Key Arteries Identification (Schematic)

Aortic arch
Right subclavian artery
Left vertebral artery
Right external carotid artery
Left internal carotid artery

5. Blood Flow Pathway: Heart to Dorsalis Pedis Artery
The pathway of a red blood cell from the heart to the top of the foot includes:

Ascending aorta
Aortic arch
Thoracic aorta
Descending aorta
Right/left common iliac arteries
Right/left femoral arteries
Right/left popliteal arteries
Right/left anterior/posterior tibial arteries
Dorsalis pedis artery

6. Blood Flow Pathway: Superior Mesenteric Vein to Right Atrium

Superior mesenteric vein
Hepatic portal vein
Liver (for filtration and nutrient processing)
Hepatic vein
Inferior vena cava
Right atrium

7. Definitions

Portal System: A network of veins connecting two capillary beds, allowing direct transport of blood between organs.
Function of Hepatic Portal System: Transports nutrient-rich blood from the digestive organs, spleen, and pancreas to the liver for filtration, detoxification, and nutrient processing.

Grading Rubric for Lab Report

Activity	Deliverable	Points
Part 1	Complete lab activities	15
Part 2	Complete lab report	15
Total	Complete all lab activities	30

References

Marieb, E. N., & Hoehn, K. (2021). Human Anatomy & Physiology (11th ed.). Pearson.

Tortora, G. J., & Derrickson, B. (2020). Principles of Anatomy and Physiology (16th ed.). Wiley.

BIOS 255 Week 3 Lab-Blood Pressure/Blood Vessel Labeling

Anatomy.TV. (n.d.). Cardiovascular system: Blood vessels. Accessed from [Your Institution’s Database].