The thin-walled, elongated, specialised parenchyma cells, which are associated with the sieve elements, are called companion cells. They are present only in angiosperms and are absent in pteridophytes and gymnosperms.
772. Which of the following is not a symptom of a heart attack?
1. Chest pain
2. Nausea and sweating
3. Numbness and aching of arms
4. Pain in legs
Option “4” is correct A heart attack-medically was known as a myocardial infarction. The symptoms of heart attack include; pain or discomfort in one or both arms, back, neck, jaws or stomach. Shortness of breath with or without chest discomforts other signs such as breaking out in a cold sweat, nausea of lightheadedness. As with men and women’s most common heart attack symptom is chest pain or discomfort.
773. Leprosy is caused by-
1. Bacteria
2. Virus
3. Fungus
4. Protozoa
Option “1” is correct Leprosy is caused by a slow-growing type of bacteria called Mycobacterium leprae (M. leprae).
774. The age of the tree, in years can be ascertained by:
1. Its weight
2. Its height
3. The number of its annular rings
4. Length of its root
Option “3” is correct The number of rings indicates the number of years the tree lived.
775. Which is the anti-coagulant substance in blood?
1. Fibrinogen
2. Heparin
3. Thrombin
4. Globin
Option “2” is correct Heparin is also known as unfractionated heparin, is medication which is used as an anticoagulant.
776. Which of the following diseases, antibodies cannot cure?
1. Leprosy
2. Tetanus
3. Measles
4. Cholera
Option “3” is correct
Measles is a highly contagious respiratory infection which is caused by a virus. It cannot be cured by antibiotics whereas leprosy, Tetanus and Cholera can be cured by antibiotics.
Option “3” is correct A mangrove is a shrub or small tree that grows in coastal saline or brackish water. They have respiratory roots.
778. Rodentia Sciurus is the scientific name of –
1. Rat
2. Platypus
3. Squirrel
4. Beaver
Option “3” is correct
Rodentia Sciurus is scientific name of Squirrel.
779. Which of the following is a symptom of hemophilia?
1. Night Blindness
2. No clotting of Blood
3. Rickets
4. Loss of hemoglobin
Option “2” is correct Haemophilia,is a mostly inherited genetic disorder that impairs the body’s ability to make blood clots, a process needed to stop bleeding.
780. The disease caused by swelling of the membrane over spinal cord and brain is-
Option “4” is correct Meningitis is a disease caused by the inflammation of the protective membranes covering the brain and spinal cord known as meninges.
