Zoology Test-4 (Medical Entrance)

In a healthy resting adult, the cardiac output of either ventricle is roughly 5 liters per minute, calculated as heart rate multiplied by stroke volume (e.g., 70 beats per minute times 70 milliliters per beat).

In biogeography, the major divisions of the Earth's surface based on flora and fauna distribution are called 'realms' (such as the Palearctic, Nearctic, Indo-Malayan realms). 'Zones,' 'epoch,' and 'era' refer to other classification systems in geology or chronology, not biogeographical regions.

The nephron is the fundamental structural and functional unit of the kidney, responsible for filtering blood and forming urine. Each kidney contains approximately 1 million nephrons in humans.

The nervous system, including nerve cells (neurons), originates from the ectoderm germ layer during embryonic development. The neural plate forms the neural tube, which gives rise to the central nervous system.

Cladistics uses shared derived characters (synapomorphies) to group organisms and construct cladograms. These evolutionary innovations help identify common ancestry and branching patterns in phylogenetic trees.

The notochord forms early in embryonic development and defines the chordate body plan. It develops before most major organs and provides structural support and signaling functions for the developing nervous system.

The sporozoite is the infectious form of the malaria parasite (Plasmodium) that enters the human body when an infected female Anopheles mosquito takes a blood meal. From the bloodstream, sporozoites travel to the liver to begin the next stage of their life cycle.

The quadriceps femoris muscle group is located on the anterior thigh, while the gastrocnemius is the prominent calf muscle on the posterior lower leg. Both are essential for walking, running, and lower body movements.

The distal convoluted tubule actively reabsorbs sodium ions (Na+) under the influence of aldosterone. While it also handles calcium reabsorption and potassium secretion, sodium is the primary ion regulated in this segment.

Shivering is an involuntary thermoregulatory response where skeletal muscles (striated muscles) undergo rapid, rhythmic contractions. This generates heat through muscle metabolism and helps maintain body temperature in cold conditions.

Hypocalcemia results from insufficient secretion of parathyroid hormone (PTH). PTH normally increases blood calcium levels by stimulating bone resorption, enhancing renal calcium reabsorption, and promoting intestinal calcium absorption through vitamin D activation.

Adrenaline (epinephrine) is called the emergency hormone because it's rapidly released during stressful situations, triggering the fight-or-flight response. It increases heart rate, blood pressure, and energy availability while redirecting blood to essential organs.

Dr. Jonas Salk developed the first successful polio vaccine in 1955. His inactivated polio vaccine (IPV) was administered by injection and proved highly effective in preventing paralytic poliomyelitis, leading to a dramatic decline in polio cases worldwide.

The spleen functions as the body's blood bank by storing platelets and red blood cells, filtering damaged blood cells, and releasing stored blood during emergencies. It also plays important roles in immune function and recycling iron from old red blood cells.

 Gonadotropins are glycoprotein polypeptide hormones secreted by gonadotrope cells of the anterior pituitary of vertebrates.This family includes the mammalian hormones follicle-stimulating hormone (FSH), luteinizing hormone (LH), and placental/chorionic gonadotropins human chorionic gonadotropin (hCG) and equine chorionic gonadotropin (eCG).

Ptyalin (salivary amylase) is the digestive enzyme secreted by salivary glands present in the buccal cavity. Trypsin and pepsin are proteases found in the stomach and small intestine, while lipase is primarily pancreatic.

The biceps (front of upper arm) and triceps (back of upper arm) muscles surround the humerus bone. Radius and ulna are forearm bones, while femur is the thigh bone.

Duramater is the outermost and toughest layer of the meninges covering the brain and spinal cord. The meningeal layers from outermost to innermost are: duramater, arachnoid, and piamater. Choroid refers to the vascular layer of the eye.

Addison's disease is caused by adrenal cortex insufficiency, leading to decreased production of cortisol and aldosterone hormones. The adrenal medulla secretes adrenaline and noradrenaline, while pituitary and thyroid are distinct endocrine glands.

Insulin is a protein hormone (polypeptide) secreted by the beta cells of pancreatic islets of Langerhans. Steroids include hormones like cortisol and testosterone, while lipids and carbohydrates are nutrient classes, not hormone types.

Eugenics is the application of genetic principles to improve the human population through selective breeding and genetic intervention. Genetic engineering involves manipulating DNA, biotechnology uses biological processes for industrial applications, and anthropology studies human societies.

Insects, including cockroaches, have an open circulatory system where hemolymph (insect blood) flows freely through body cavities (hemocoels) rather than being confined to blood vessels. Closed circulatory systems are found in vertebrates like humans and earthworms.

Metachrosis is the physiological ability to change skin color, most prominently found in amphibians like chameleons and frogs. Mammals and birds generally lack this capability, making 'All of these' incorrect.

Gangliosides are glycosphingolipids predominantly found in nerve cell membranes, particularly in the brain and nervous tissue. They play crucial roles in cell signaling and neural function. Option C 'carolia' appears to be a typo, possibly meaning 'cardiac'.

Achondroplasia is an autosomal dominant disorder. When healthy (normal height) parents produce a child with achondroplasia, it results from a spontaneous (new) mutation in the gametes or early embryo. Point mutation is a type of mutation mechanism, while induced mutation refers to artificially caused changes.