Answer:
Chromosomal DNA is packaged inside microscopic nuclei with the help of histones. These are positively-charged proteins that strongly adhere to negatively-charged DNA and form complexes called nucleosomes. ... Nucleosomes fold up to form a 30-nanometer chromatin fiber, which forms loops averaging 300 nanometers in length.
Explanation:
Answer:
The Mitral/Bicuspid Valve
Explanation:
The heart is composed of 4 chambers: left and right atria, and left and right ventricles. The “right heart” (right atrium and ventricle) receives deoxygenated blood from the systemic circulation through the Vena Cava, and impels this blood towards the lungs through the Pulmonary Arteries where it will be oxygenated. The “left heart” (left atrium and left ventricle) receives oxygenated blood from the pulmonary circulation through the Pulmonary veins and impels this blood towards the systemic circulation through the Aorta artery.
The systemic and pulmonary circuits work in series, and maintaining the unidirectional course of the blood flow is very important. This can be done by the presence of fibrous valves that are present between the atrium and the ventricles, and in between the ventricles and the Pulmonary/Aorta artery.
The location of these structures are as follows:
Systemic circulation ⇒ Right Atrium → [Tricuspid Valve] → Right Ventricle → [Pulmonary Valve] → Pulmonary Artery ⇒ Pulmonary circulation
Pulmonary circulation ⇒ Left Atrium → [Mitral/Bicuspid Valve] → Left Ventricle → [Aortic Valve] → Aorta ⇒ Systemic circulation
Answer: a. epicondyles
Explanation:
Distally the humerus bone is flattened. It exhibit a prominent bony projection on the medial side it is called as the medial epicondyle of the bone. The lateral epicondyle is present on the lateral side of the distal part of the humerus bone.
The grasping and powerful muscles of the forearm are attached with the medial epicondyle. It is typically robust and larger as compared to the lateral epicondyle. The lateral epicondyle is attached with the weaker muscles attached posteriorly.
Quartz sand and Black sand are the most common. Each type is formed by rocks breaking down from weathering.