Life Processes Test - 19

a

• An amylase is an enzyme that catalyses the hydrolysis of starch into sugars. Amylase is present in the saliva of humans and some other mammals.
• Pepsin is the powerful enzyme in gastric juice that digests proteins such as those in meat, eggs, seeds, or dairy products.
• Three enzymes found in pancreatic juice, called trypsin, chymotrypsin and carboxypeptidase, are the pancreatic enzymes that complete the digestion of proteins. Because proteins are held together by peptide bonds, these enzymes work by breaking peptide bonds.
• The ileum and the jejunum parts of the small intestines secrete a combination of several enzymes called succus entericus. Succus entericus contains sucrose which is used in the breakdown of sucrose into fructose and glucose.

Iron (Fe) atom is present in Fe²⁺ or Fe³⁺ oxidation states in the centre of porphyrin ring of 'heme' group.The heme group (a component of the hemoglobin protein) is a metal complex, with iron as the central metal atom, that can bind or release molecular oxygen.

• The epiglottis is a flap made of elastic cartilage covered with a mucous membrane, attached to the entrance of the larynx. It projects obliquely upwards behind the tongue and the hyoid bone, pointing dorsally. It stands open during breathing, allowing air into the larynx. During swallowing, it closes to prevent aspiration, forcing the swallowed liquids or food to go down the esophagus instead. It is thus the valve that diverts passage to either the trachea or the esophagus.
• Platelets are the cells that circulate within our blood and bind together when they recognise damaged blood vessels. When you get a cut, for example, the platelets bind to the site of the damaged vessel, thereby causing a blood clot. There’s an evolutionary reason why they’re there. It’s to stop us from bleeding
• Electro cardiograph is an instrument used in the detection and diagnosis of heart abnormalities that measures electrical potentials on the body surface and generates a record of the electrical currents associated with heart muscle activity. Also called cardiograph.
• A sphygmo manometer, also known as a blood pressure meter, blood pressure monitor, or blood pressure gauge, is a device used to measure blood pressure, composed of an inflatable cuff to collapse and then release the artery under the cuff in a controlled manner,and a mercury or mechanical manometer to measure the pressure.

Osmoregulation is the active regulation of the osmotic pressure of an organism's body fluids to maintain the homeostasis of the organism's water content; that is, it maintains the fluid balance and the concentration of electrolytes (salts in solution) to keep the fluids from becoming too diluted or concentrated.

The sieve tubes, the companion cells and the phloem parenchyma represent the living components of the tissue while phloem fibres represent the only nonliving component of the tissue. Phloem is commonly described as a living, complex permanent tissue.

Green plants make their own food by the process of photosynthesis. Chlorophyll, the green pigment found in chloroplasts, traps light energy from the sun. The plant also takes in raw materials from the environment, water through its roots and carbon dioxide moves into the stomata by diffusion.

• The aorta is an artery that conveys oxygenated blood from the heart to other parts of the body.
• While veins usually carry deoxygenated blood from tissues back to the heart, in this case, pulmonary veins are among the few veins that carry oxygenated blood instead. Oxygenated blood from the lungs is circulated back to the heart through the pulmonary veins that drain into the left atrium.

Heterotrophs are most abundant in nature. They do not synthesize their own food but depend on other organisms or on dead organic matter for food. They may be parasites, saprophytes or symbiontes.

Pneumatophores are specialized ‘breathing’ roots that develop in some plant species growing in waterlogged or strongly compacted soils, e.g. mangroves. The aerial part of the root contains many pores, enabling gas exchange with the atmosphere. Internally, a well developed system of intercellular spaces allows gases to diffuse throughout the submerged portion of the roots. Because these roots are exposed and not submerged underwater, the root system performs the function of obtaining oxygen which is otherwise difficult to obtain from the water-looged soil.