General
The life of red blood cells is?
A) 45 days
B) 120 days
C) 125 days
D) 145 days
Red blood cells (RBCs), also known as erythrocytes, have an average lifespan of about 120 days in the human body. They are responsible for transporting oxygen from the lungs to tissues and carrying carbon dioxide back to the lungs for exhalation.
RBCs lack a nucleus and most organelles, which allows more space for hemoglobin but limits their ability to repair themselves. Over time, they become less flexible and are eventually removed from circulation by the spleen and liver.
The body continuously produces new RBCs in the bone marrow to replace the old ones. This balance ensures a stable supply of oxygen to tissues.
Other options such as 45, 125, and 145 days are incorrect as they do not match the established average lifespan.
Thus, 120 days is the correct answer. This concept is important in understanding blood physiology, anemia, and overall human health.
General
A)
May 1991
B)
June 1992
C)
May 1992
D)
April 1995
The Rio Earth Summit was held in June 1992 in Brazil and focused on sustainable development and environmental protection.
General
A)
1st
B)
2nd
C)
3rd
D)
4th
Kurt Waldheim served as the fourth Secretary-General of the United Nations from 1972 to 1981. The Secretary-General is the chief administrative officer of the UN and plays a key role in international diplomacy.
Waldheim’s tenure focused on global peace efforts and conflict resolution during the Cold War period. His role involved mediating disputes and representing the UN on international platforms.
Thus, he is ranked as the 4th Secretary-General, making option D correct.
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General
A)
1300 kms
B)
1600 kms
C)
1900 kms
D)
2100 kms
Karakoram Highway length is about 1600 km connecting Pakistan and China.
General
A)
Stomach
B)
Duodenum
C)
Jejunum
D)
Anus
The pancreas is a vital digestive organ that produces enzymes necessary for breaking down food. These enzymes include amylase (for carbohydrates), lipase (for fats), and proteases such as trypsin (for proteins). The pancreas releases these enzymes into the duodenum, which is the first part of the small intestine.
The enzymes travel through the pancreatic duct and mix with bile and partially digested food in the duodenum. This is where most chemical digestion occurs. The environment in the duodenum is alkaline, which is suitable for pancreatic enzyme activity.
The stomach primarily performs mechanical digestion and uses acid and pepsin for protein breakdown. The jejunum mainly absorbs nutrients, while the anus is involved in excretion.
Thus, the duodenum is the correct answer. Understanding the digestive system’s structure and function is important in biology and helps explain how nutrients are processed and absorbed in the body.
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General
A)
1796
B)
1976
C)
1980
D)
1767
Edward Jenner, an English physician, is credited with developing the first successful vaccine in 1796. He discovered that milkmaids who had contracted cowpox were immune to smallpox, a deadly disease at the time.
Jenner tested his theory by inoculating a young boy with material from cowpox lesions and later exposing him to smallpox. The boy did not develop the disease, proving immunity.
This discovery laid the foundation for immunology and modern vaccination. It led to the eventual eradication of smallpox worldwide.
Other options are incorrect as they do not match the historical timeline.
Thus, 1796 is the correct answer, marking a major breakthrough in medical science and public health.
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