Advanced Placement (AP) Biology Practice Exam

The type of fat most likely to contribute to cardiovascular diseases includes both saturated fats and trans fats. Saturated fats, which are typically found in animal products and some tropical oils, can raise levels of LDL (low-density lipoprotein) cholesterol in the bloodstream. Elevated LDL cholesterol is recognized as a significant risk factor for cardiovascular diseases because it can lead to the buildup of plaque in arteries, contributing to conditions like atherosclerosis.

Trans fats, which are often found in partially hydrogenated oils, are particularly harmful because they not only raise LDL cholesterol but also lower HDL (high-density lipoprotein) cholesterol, which is protective against heart disease. The combination of these effects leads to an increased risk of cardiovascular diseases, making both saturated and trans fats problematic in the diet.

While unsaturated fats are generally considered heart-healthy and can actually help improve cholesterol levels and decrease inflammation when consumed in moderation, the question specifically points to the detrimental effects of saturated and trans fats. Thus, both classes contribute to cardiovascular health risks.