Heart Dissection Lab: Mr. Bradley’s Anatomy Class

(Submitted by CHS Junior, Cali Hendrickson)

This week in Mr. Bradley’s Anatomy class, students rolled up their sleeves and got an up-close look at one of the most important organs in the human body—the heart. As part of our cardiovascular system unit, as a class, we participated in a hands-on heart dissection to explore the structure and function of this powerful muscular pump.

The heart dissection lab aimed to:

1. Identify and describe the external and internal anatomy of the heart.

2. Understand the flow of blood through the heart and its major vessels.

3. Compare the anatomy of a preserved heart to textbook diagrams.

External Heart Examination

Students began by observing the external structures of the heart. With guidance from Mr. Bradley, we located and identified major blood vessels connected to the heart:

• Aorta – the large artery that carries oxygenated blood from the heart to the body

• Pulmonary trunk – which splits into pulmonary arteries carrying deoxygenated blood to the lungs

• Vena cava (superior and inferior) – veins bringing deoxygenated blood back to the heart

• Pulmonary veins – carrying oxygenated blood from the lungs to the heart

The orientation of the heart was discussed, with students learning how to distinguish the front (anterior) and back (posterior) as well as the right and left sides.

Using Pencils to Explore the Ventricles

One of the most memorable and helpful parts of the lab was when Mr. Bradley instructed us to use pencils as tools to explore the ventricles of the heart.

• Students carefully inserted pencils into the right and left ventricles to trace the path that blood would take through each chamber.

• This helped clearly identify the openings to major vessels, such as the pulmonary artery from the right ventricle and the aorta from the left ventricle.

• By placing the pencil through these structures, students could visualize how blood flows upward through the valves and out to the lungs or the body.

• It also made it easier to differentiate the thicker-walled left ventricle from the right, reinforcing the idea that the left side must pump blood to the entire body.

Dissecting the Heart

Next came the most exciting part—cutting into the heart to view its internal structures.

1. Initial Cut
   We used a scalpel or scissors to make a longitudinal incision along the right side of the heart, revealing the right atrium and right ventricle. They identified the tricuspid valve, which prevents backflow of blood between these chambers.
   
   

2. Left Side Exploration
   A second incision on the left side revealed the left atrium and left ventricle. Here, students located the bicuspid (mitral) valve and observed the thicker muscular wall of the left ventricle, built to pump blood throughout the entire body.
   
   

3. Valves and Chordae Tendineae
   We examined the valves that direct blood flow and the chordae tendineae—string-like tissues anchoring the valves to the heart walls. These structures ensure that valves open and close properly during contractions.
   
   

4. Tracing Blood Flow
   As we explored, we traced the path of blood through the heart:
   
   

• Deoxygenated blood enters the right atrium via the vena cava

• Moves to the right ventricle and exits through the pulmonary arteries to the lungs

• Oxygenated blood returns via pulmonary veins to the left atrium

• Then moves into the left ventricle and exits through the aorta to the body

Conclusion

Mr. Bradley’s heart dissection lab was a hands-on success, giving us a literal and educational look into the heart of the circulatory system. Not only did we walk away with a greater appreciation for this vital organ, but they also built a stronger understanding of how form supports function in human anatomy.

'It's A Big Deal Day' Day of Testing April 8th

 *Please note that students will be dismissed as early as 12:30p on April 8th after all testing. Lunch will be provided at 12:25.

Student Schedule - April 8th

Seniors

7:55 Senior Day @ Auditorium

Speaker Schedule TBD

12:20 Dismiss following lunch

Juniors   **Must have chromebooks fully charged**

(Absent students will make up the test on Thursday, April 18th.)

7:55 Report to rooms for instructions

8:05 Test 1 - English (45 minutes) - no break following

8:50 Test 2 - Math (5 min directions, 60 min test)

10:00 15-minute Morning Break 

10:15 Test 3 - Reading (5 min directions, 35-minute test) - no break

10:55 Test 4 - Science (5 min directions, 35-minute test)

11:35 5-minute break

11:40 Test 5 - Writing (5 min directions, 40-minute test)

12:25 Lunch/Dismissal

Sophomores

7:55 Report to rooms for instructions

8:10 Review John Baylor Test Taking Tips for English/Reading

8:20 Test 1 - English (5 min instructions, 30 minute test time)

8:55 5 minute break

9:00 Review John Baylor Test Taking Tips for Math

9:10 Test 2 - Math (5 min instructions, 40 minute test time)

9:55 15 minute Morning Break

10:10 Test 3 - Reading (5 min directions, 30 minute test) - no break

10:50 Test 4 - Science (5 min directions, 30 minute test)

11:25 5 minute break

11:30 Test 5 - Writing (5 min directions, 40 minute test)

12:25 Lunch/Dismissal

Freshman **Must have chromebooks fully charged**

*Tests are not timed so students can finish tests after breaks if needed

(Absent students will be rescheduled for testing, TBD)

7:55 Report to rooms

8:00 Test 1 - Reading - no break

9:15 Test 2 - Science

10:00 15 minute Morning Break

10:15 Test 3 -  Math - no break

11:30 Test 4 - Language Usage

12:30 Lunch/Dismissal

Summer Driver Education Registration Released

The Summer 2025 driver education dates are available on the Nebraska Safety Center’s website www.unk.edu/dred. Registration is now open!

 

Due to a continuing instructor shortage, there have been some changes to the programs offered this summer with some programs not being offered. Please encourage your students to register early to avoid missing out on an in-person class. In addition to the in-person classes, the Safety Center is offering an online driver education course that can be taken at any time.

A copy of the registration brochure is available at the high school office; however, the preferred method of registration is from our website: www.unk.edu/dred then click on the location of your choice. Please contact the Safety Center with any questions at 308-865-8256.

 

DeAnn Keith

Program Coordinator

Nebraska Safety Center

University of Nebraska

Kearney NE 68849-4550

308-865-8562

Anatomy Class Dissects Sheep Brain

(Submitted by CHS Junior, Cali Hendrickson)

Sheep Brain Dissection: Mr. Bradley’s Anatomy class worked on an exciting journey into the inner workings of the brain with a hands-on sheep brain dissection. The objective was to identify and describe the principal structures of the sheep brain. This engaging activity offered students an opportunity to observe the complexity of the nervous system firsthand.

Examination of the Sheep Brain The dissection began with an external examination of the sheep brain. Interestingly, the sheep brain is quite similar to the human brain in structure but differs in size and orientation. The sheep brain is elongated with an anterior-to-posterior orientation, while the human brain is positioned more vertically.

Dura Mater Removal The tough outer covering of the brain, known as the dura mater, was carefully removed. This membrane protects the brain but must be taken off to view the underlying structures.

Identification of the Cerebrum The cerebrum, the most prominent part of the brain, was observed. It is divided into two nearly symmetrical hemispheres by the deep longitudinal fissure.

Observation of the Gyrus and Sulcus The surface of the cerebrum is covered in folds known as gyri and grooves called sulci. These folds increase the surface area of the brain, allowing for more complex neural connections.

Cerebellum Examination At the back of the brain lies the cerebellum, responsible for balance and coordination. Its smaller gyri distinguish it from the cerebrum.

Exploring the Ventral Surface Turning the brain over revealed several crucial structures: -Optic Chiasma: An X-shaped structure where optic nerves cross, crucial for vision. -Pituitary Gland: Although often removed with the dura mater, its location below the optic chiasma was noted. -Olfactory Bulbs: Located at the front of the brain, responsible for the sense of smell.

Dissection of the Internal Brain A longitudinal incision along the deep longitudinal fissure was made to examine the internal structures to separate the brain into the left and right hemispheres. This revealed:

Corpus Callosum The bundle of nerve fibers connecting the two cerebral hemispheres is crucial for communication between the brain’s halves.

Thalamus and Hypothalamus These structures were visible beneath the corpus callosum. The thalamus acts as a relay center for sensory signals, while the hypothalamus regulates vital bodily functions like temperature and hunger.

Pineal Gland and Third Ventricle The pineal gland, involved in regulating sleep cycles, was observed near the third ventricle, a cavity containing cerebrospinal fluid.

Conclusion Mr. Bradley’s Anatomy class successfully completed the sheep brain dissection, gaining a deeper understanding of the brain’s intricate design and functionality. This hands-on experience not only enhanced their knowledge but also sparked curiosity about the wonders of neuroscience.

Stay tuned for more exciting explorations in Anatomy from Mr. Bradley’s classroom!