Facts on red blood cells and hemoglobin

len Alfred Ajibola - Fri, 14th June, 2019 @ 9:28 PM

Topics in Biology

Tropical savanna explained with its characteristics Ecological pyramid explained with its importance and limitations Hindbrain: Medulla Oblongata and its features Food web explained with examples Biology Scheme of Work, SS1, First Term Biology Scheme of Work, SS1, 2nd Term Biology Scheme of Work, SS1, 3rd Term Male accessory sex organs: Seminal vesicles and bulbourethral glands Scrotum and its contents: Testicles Brain: Introduction to the human brain Forebrain: Lobes of the cerebrum and their functions Cerebellum: Parts and functions of the cerebellum Midbrain: Division and functions of the midbrain Negative feedback mechanism in homeostasis Arterial disorders explained with their causes Types of desert and their characteristics Characteristics of tropical rainforest Swamp forest: What are swamp forests? Characteristics of swamp forests Savanna biome: Concept of the savanna

Academic Questions in Biology

Please check out our Test Your Knowledge page to see all Questions and Answers

In a food chain, the primary consumers are classified under trophic level  _____.

  • A. Zero

  • B. One

  • C. Two

  • D. Three

  • E. Four

  • F. Five

Cold blooded animals are referred to as _____.

  • A. Homeotherms

  • B. Endotherms

  • C. Poilokitherms

  • D. Ectotherms

  • E. Thermotherms

  • F. None of the above

All reptiles are vertebrates.

  • A. True

  • B. False

_____ cells are responsible for the formation of osteoblasts.

  • A. Osteocytes
  • B. Chondrocytes
  • C. Chondroblasts
  • D. Osteoclasts
  • E. Osteoprogenitor cells
  • F. Osteoblastic

_____ is a bone that constitute the axial skeleton.

  • A. Clavicle
  • B. Scapula
  • C. Patella
  • D. Radius
  • E. Sternum
  • F. Femur

Which of the following is false concerning cartilages and bones?

  • A. Cartilage does not have a direct blood supply while bones have direct blood supply
  • B. The process of ossification replaces a cartilage to bone
  • C. The protein that makes up cartilage is called chondrin while that that makes up bone is called ossein
  • D. Cartilage grows from both ends while bones grow from one of its epiphysis
  • E. They both have living cells within them
  • F. Haversian system is absent in cartilage but present in bones

A diagram showing the movement of energy through a food chain is called a _____.

  • A. Food Chain
  • B. Food Web
  • C. Food Energy
  • D. Food Link
  • E. Food Flow
  • F. Food Pyramid

Which of the following is NOT a part of the wrist bones (or carpal bones)?

  • A. Cuboid
  • B. Scaphoid
  • C. Hamate
  • D. Triquetral
  • E. Pisiform
  • F. Trapezium



Read more on its smart academic features here

Red Bood Cells and Hemoglobin:

When we reflect on some of the basic necessities of life, oxygen (O2) will definitely rank among the top.

Although oxygen makes up about 21% of the atmosphere, it is still enough to make earth a livable planet for its different inhabitant.

Please read on layers and composition of the atmosphere here.

In humans, without the red blood cell and hemoglobin, atmospheric oxygen will be considered a waste because the various bodily cells, tissues and organs will not be able to utilize it for respiration. Meanwhile, understand that breathing and respiration aren't the same thing.

Breathing is simply when one inhales and exhales air. Everytime we breathe, oxygen is inhaled while carbon(IV)oxide is exhaled.

Respiration is the use of inhaled oxygen to break down food (glucose) in order to generate energy in the form of ATP (Adenosine TriPhosphate).

Please read on the basic characteristics of life here.

Facts on Red Blood Cells and Hemoglobin

In order to ease our explanations on red blood cells and hemoglobin, we will look at some of the facts pertaining both.

Below are some of these facts:

  • The red blood cell can also be referred to as an erythrocyte.

  • The red blood cells are one of the solid components of the blood; the others are: 'white blood cells' and 'platelets'.
  • Note: Blood is a mixture. It is made up of a liquid termed plasma and solid (called cells). Based on this fact, a blood can be dried and grounded to form a blood meal.

    Please read on the separation of blood into its various components here.

  • An average human being produces up to 2.5 million red blood cells per second.

  • Ordinarily, the blood is light or pale yellow in color. It is the red blood cells that gives the blood its red coloration.

  • The red blood cell has the shape of a biconcave disc with a thickness of 2.5 micrometers at its edges and less than 1 micrometer at its center.
  • The image below illustrates the shape and diameter of the red blood cell:

Red Blood Cell - Len Academy

  • The red blood cell is very flexible. As a result, it can squeeze through blood capillaries by altering its shape without destroying itself.
  • Understand that capillaries are tiny and microscopic blood vessels that operate at the cellular level. You can think of a blood vessel as a pipe that carries blood within our body system.

    Apart from the capillaries, other blood vessels are the arteries and veins.

    Read on the layers of an artery here.

  • A mature red blood cell has no nucleus. Instead, it contains hemoglobin within it.

  • Some scientists are of the opinion that if the matured red blood cells had a nucleus, the nucleus would be damaged when the red blood cells attempt to pass through the blood capillaries. This damaged nucleus will result in the sudden death of the red blood cell.

  • Red blood cell has no DNA, RNA, mitochondria or other organelles found in most cells. For this reason, it does not require energy to carry out its functions. This is true because the mitochondria which is often referred to as power house of the cell is absent.
  • Please read on interesting facts for students here.

  • In the early weeks of embryonic life, the red blood cells are produced in the yolk sac. They contain nucleus at this point in time.

  • During the 3rd to 8th months of pregnancy, the red blood cell is produced mainly in the liver.
  • The spleen and lymph nodes also produces some red blood cell during this period.

  • During the last month of pregnancy and after birth, the red blood cells are produced exclusively in the bone marrow.
  • Please read on the bones of the human skeleton here.

  • After age 20, the long bones of the human body stop producing red blood cells.
  • Examples of long bones are humerus (bone of the arm) and femur (bone of the thigh).

    During this period (after age 20), the red blood cells are now produced in the membranous bones. Examples of membranous bones are the vertebrae, sternum and ribs.

    Please read on the types of bone here.

  • The major function of the red blood cell is to transport hemoglobin. This implies that hemoglobin is always present inside a matured red blood cell.

  • It is the hemoglobin in the red blood cell that binds with oxygen to form oxyhemoglobin.
  • Note: The red blood cell has other functions too. For instance, they initiate the transport of CO2.

    The transport of carbon(IV)oxide by hemoglobin is made possible because it contain an enzyme called carbonic anhydrase which catalyzes the reversible reaction between carbon(IV)oxide (CO2) and water (H2O) to form carbonic acid (H2CO3). It is in this form that CO2 is transported back to the lungs for expiration.

  • The red blood cells bind more strongly to carbon(II)oxide or carbon monoxide (CO) in comparison to the rate at which oxygen binds to hemoglobin. This is why death is very rapid during carbon monoxide poisoning.

  • Red blood cells are red when hemoglobin (present within it) is combined with oxygen to form oxyhemoglobin.
  • They become blue after the oxygen had been delivered to the body cells.

    Please read on some amazing facts in biology here.

  • An average man has 5,200,000 red blood cells per cubic millimeter of blood.

  • An average woman has 4,700,000 red blood cells per cubic millimeter of blood.

  • Erythropoietin is a hormone that stimulates the production of red blood cells.
  • Erythropoietin is produced in the kidneys and an increase in its production is trigged during hypoxia.

    Hypoxia is a condition where there is very little amount of oxygen in the blood; and as a result, the body tissues consequently lack oxygen.

    You can read on homeostasis here.

  • Iron is vital in the formation of hemoglobin. This is why it is always present in blood capsules; and often recommended by medics for blood building.

  • The red blood cells have an average lifespan of 120 days. They are eventually destroyed by the liver and spleen respectively.

  • Anemia results when there is little or no hemoglobin in the blood.
  • Anemia will also occur when there are too few red blood cells in the blood.

  • Polycythemia is the presence of numerous (excessive) red blood cells in the blood. This condition is seen in people that live in high altitude.
  • Note: The higher the altitude, the lower the atmospheric oxygen.

  • Polycythemia vera (also called erythremia) is a medical condition where there are excessive red blood cells in the blood as a result of genetic aberration.

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Alfred Ajibola is a Medical Biochemist, a passionate Academician with over 10 years of experience, a Versatile Writer, a Web Developer, a Cisco Certified Network Associate and a Cisco CyberOps Associate.

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Amazing facts in Biology

Panda eating bamboo - Len Academy

99% of a panda's diet is bamboo. They may eat fish or other small animals occasionally

When attacked by insects, lima beans plant will often command parasitic wasps to their defence.

When the leaves of the lima bean's leaves are eaten by insects, the plant gives off a substance that signals parasitic wasps to swam in, destroying its enemies (the leaf-eating insects) in the process

Frogs drink water through their skin

Armadillos - Len Academy

Armadillos are western mammals known for their unique armor-like shell which are bulletproof

Polka-dotted zebra - Len Academy

Although zebras are known for their characteristics black and white stripes, we still have some polka-dotted zebras

Charles Darwin is a British naturalist and biologist who contributed greatly into the study of evolution. According to research, he frequently ate the animals he studied

Lungs are the only human organ that can float on water

Unlike most snakes that lay eggs, anacondas give birth to live babies

Shrimp - Len Academy

A shrimp's heart is in its head

Women have more pain receptors than men


For a thing to be considered living, it must possess all the basic characteristics of life. These include:

  1. Movement

  2. Respiration

  3. Nutrition

  4. Irritability or Sensitivity

  5. Growth

  6. Excretion

  7. Reproduction

  8. Death

  9. Adaptation

  10. Competition

Please read the explanations on all the basic characteristics of life here

During strenuous exercises like sprinting or running, your body may actually work in the shortage of oxygen. During this time, your body owes oxygen (called oxygen debt) and it must be replenished or repayed after the exercise is stopped. This is why you breathe excess of oxygen after you stopped the exercise.

This is the concept of anaerobic respiration

Food Chain - Len Academy

A food chain is a diagram that shows the relationship between plants and animals within a habitat on the basis of how they rely on each other for food.

Note: Habitat is a place where an organism live. It is of three types:

  • Terrestrial (Land)
  • Aquatic (Water)
  • Arboreal (Treetops)

You can read on food chain here

The term Biology originated from two Greek words. They are:

  • Bios: means life.

  • Logos: means knowledge or to study.

Biology can therefore be defined as the study of life

Anything that has life is generally considered as a living organism (or organism). All living organisms must be able to carry the following activities:

  1. Movement

  2. Respiration

  3. Nutrition

  4. Irritability or Sensitivity

  5. Growth

  6. Excretion

  7. Reproduction

  8. Death

  9. Adaptation

  10. Competition

The above listed points are often regarded as the basic characteristics of life. You can memorize them using the acronym -> MR. NIGER DAC.

You can read on the introduction to biology and the basic characteristics of life here

The gas used in the manufacture of food by plants is Carbon dioxide or Carbon(IV)oxide or CO2

Plants manufacture food through a process called photosynthesis.

Please read on photosynthesis here

It is noteworthy to state that plants are the only orgnisms that take away CO2 from the atmosphere