Artery histological structure: 1. Arteries are thick-walled vessels carrying oxygenated blood (except for the pulmonary artery, which carries deoxygenated blood to the lungs for oxygenation). 2. All arteries originate from the heart and transport blood away from it. 3. Arteries consist of three layers: tunica externa, tunica media, and tunica interna. 4. Tunica externa (adventitia) … Read more
1. During systole, the heart exerts pressure, propelling blood into the aorta, initiating blood circulation throughout the body. The aorta branches into the dorsal aorta, supplying the upper body before dividing into arteries that extend into the legs. Blood moves in the legs due to pressure and gravitational forces. 2. Muscles in the legs play … Read more
1. It takes 0.8 seconds to complete a single cardiac cycle. 2. The cardiac cycle comprises three crucial phases: atrial systole, ventricular systole, and joint diastole. 3. Under normal conditions, atrial systole lasts for 0.1 second, followed by ventricular systole lasting 0.3 seconds, and joint diastole, or complete diastole, extending for approximately 0.4 seconds. 4. … Read more
1. The aorta, originating from the left ventricle of the heart, carries blood rich in oxygen. 2. Deoxygenated blood undergoes oxygenation in the pulmonary capillaries surrounding the lung’s alveoli. The resulting oxygenated blood is collected by the four pulmonary veins. 3. These pulmonary veins transport the oxygenated blood to the left atrium of the heart. … Read more
Cardiac output refers to the amount of blood ejected per minute in a typical adult human.It is calculated as follows: Cardiac output = Heart rate × Stroke volume Given : Cardiac output = 5500 cm³ Pulse rate = Heart rate = 68 By using these values stroke volume of is calculated as follows: ∴ Cardiac … Read more
1) The contraction of the heart generates a pulsating pressure, akin to a wave, pushing blood out of the heart. This pulsation is what you feel as the pulse. However, this pressure is not constant. 2) During systole, when the heart pumps blood, the arteries experience maximum pressure. As this pressure diminishes in capillaries and … Read more
(1) Indications suggest that Shreyas might be experiencing allergic reactions, possibly due to exposure to allergens like pollen, dust, pet dander, or other environmental substances during his time in the garden. Alternatively, Shreyas, if already an asthma patient, could be facing exacerbated symptoms due to the wintry climate. (2) When a person is allergic to … Read more
1. Working with the car engine running in a closed garage suggests that Smita might be experiencing carbon monoxide poisoning. 2. Carbon monoxide (CO) is a dangerous gas formed when fuels burn incompletely in automobile engines. 3. Due to haemoglobin’s strong attraction to carbon monoxide, it forms a stable compound called carboxyhaemoglobin. This reduces available … Read more
1. Nitrogen fixation is the process of converting atmospheric nitrogen into nitrogenous salts, rendering it accessible to plants for uptake. 2. When living organisms participate in the nitrogen fixation process, it is termed biological nitrogen fixation. 3. Predominantly carried out by prokaryotic organisms, particularly various bacteria in the soil, biological nitrogen fixation is a crucial … Read more
Plants, categorized based on their photoperiodic response, fall into three distinct groups: Short Day Plants (SDP), Long Day Plants (LDP), and Day Neutral Plants (DNP). 1. Short Day Plants (SDP): i. Flowering in SDPs occurs when the photoperiod is shorter than the critical length, typically during winter and late summer. ii. SDPs, also known as … Read more