Answer: The correct answer to the question is option D
ISCHEMIC HEART DISEASE.
Explanation: To answer the question effectively, let us look at the options given,what they are and how they affect the heart.
Endothelial cells play a crucial role in the regulating vascular tone,They do so by secreting variable amounts of constricting and relaxing factors inorder to control tissue perfusion.
Hypertension on the other hand occurs as a result of factors that varies distinctively and not all related to vascular tone.
Dysrhythmias on it's own will affect the function and conduction of heart chambers but not necessarily vascular tones.
Truncus arteriosus results in only in one large artery exiting/leaving the heart.
Answer: The answer is (D) usually made of tough fibers
Explanation:
The statement "oceanic conditions determine human activities" may be interpreted in many ways.
1. Oceanic conditions determine human activities in that the moon cycle influences the tide. As the moon cycle is said to greatly influence human activity, and the tide changes as the moon does, it may also be concluded that the tides have a similar influence on human activity.
2. Weather conditions may also influence oceanic conditions.
a) Hurricanes and typhoons occur in the ocean and if they make landfall, humans are sometimes required to evacuate the location they will affect. The process of evacuation, and the reparations necessary to human civilization afterward, are both examples of oceanic conditions being influential to human activity.
b) Flooding and tsunamis may also result in evacuation, and damage to human civilization.
c) Global warming, which is resulting in the melting of the polar ice caps, contributes to rising sea levels. Rising sea levels are also oceanic conditions that may affect human civilization in the forms of flooding, erosion, and the ocean expanding, and also determine human activities.
The statements that are true of heterogeneous mixtures are: they settle out and the proportions of solute to solvent may vary. The correct answer is option A. 1 and 2. Heterogeneous mixtures are considered mixtures wherein the components are not uniform and still retain their properties. Characteristics of heterogeneous mixtures are: the ratio of solute and solvent is not equal, the substances can be separated physically and they still retain their properties even if mixed with another substance.
