Cardiac muscle tissue is unique to the heart and has a similar structure to skeletal muscle but works involuntarily like smooth muscle. Hardening of the arteries, called atherosclerosis, is caused by the formation of plaques on artery walls from factors like genetics, age, smoking, diet, and obesity. These plaques can trigger blood clots that block blood flow through arteries.

1. OPTION D
PART 4: The Heart

3. • Cardiac muscle tissue is unique to the heart.
• Their structure is like skeletal muscle cells.
• But they work involuntary like smooth muscle
cells.

30. Results
• Hardening of arteries is called atherosclerosis.
• The formation of plaques or atheromas on the
inner lining of arteries.
• Plaques trigger the a clot, or thrombosis which
can block the blood flow through the artery.

31. Consequences

34. Causes
• Genetic precondition.
• Old age less flexible blood vessels.
• Post-menopause low level of estrogen.
• Smoking
• A high salt diet and alcohol
• High amount of saturated fat and cholesterol
consumption.
• Obesity.