Definitions on Science Subject Biology

Definitions on Science Subject Biology

1. Biology:
   Biology is the branch of science that studies living organisms and life processes.
   Example: Studying plants and animals is biology.

2. Living Organism:
   A living organism is any being that has life and can grow and reproduce.
   Example: Humans are living organisms.

3. Non-living Thing:
   Non-living things do not have life and cannot grow or reproduce.
   Example: A stone is a non-living thing.

4. Cell:
   A cell is the smallest unit of life in all living organisms.
   Example: The human body is made up of cells.

5. Tissue:
   A tissue is a group of similar cells that work together to perform a function.
   Example: Muscle tissue helps in movement.

6. Organ:
   An organ is made of different tissues working together to perform a specific function.
   Example: The heart is an organ.

7. Organ System:
   An organ system is a group of organs working together to perform a major function.
   Example: The digestive system helps in digestion.

8. Growth:
   Growth is the increase in size and number of cells in an organism.
   Example: A baby grows into an adult.

9. Respiration:
   Respiration is the process by which living organisms release energy from food.
   Example: Humans breathe in oxygen for respiration.

10. Nutrition:
    Nutrition is the process by which organisms obtain and use food.
    Example: Plants make their own food by photosynthesis.

11. Photosynthesis:
    Photosynthesis is the process by which green plants make food using sunlight.
    Example: Leaves prepare food during photosynthesis.

12. Excretion:
    Excretion is the process of removing waste products from the body.
    Example: Humans excrete waste through urine and sweat.

13. Reproduction:
    Reproduction is the process by which living organisms produce new ones of their kind.
    Example: Plants reproduce by seeds.

14. Stimulus:
    A stimulus is any change that causes a response in an organism.
    Example: Touching a hot object is a stimulus.

15. Response:
    A response is a reaction shown by an organism to a stimulus.
    Example: Pulling the hand away from heat is a response.

16. Habitat:
    A habitat is the natural home of a plant or animal.
    Example: A pond is the habitat of fish.

17. Adaptation:
    Adaptation is a special feature that helps an organism survive in its habitat.
    Example: Camels have adaptations to live in deserts.

18. Ecosystem:
    An ecosystem includes living organisms and their non-living surroundings.
    Example: A forest is an ecosystem.

19. Producer:
    A producer is an organism that makes its own food.
    Example: Green plants are producers.

20. Consumer:
    A consumer is an organism that depends on others for food.
    Example: Animals are consumers.

21. Herbivore:
    A herbivore is an animal that eats plants.
    Example: A cow is a herbivore.

22. Carnivore:
    A carnivore is an animal that eats other animals.
    Example: A lion is a carnivore.

23. Omnivore:
    An omnivore is an animal that eats both plants and animals.
    Example: Humans are omnivores.

24. Food Chain:
    A food chain shows how energy passes from one organism to another.
    Example: Grass → deer → lion.

25. Food Web:
    A food web is a group of interconnected food chains.
    Example: A forest food web includes many animals and plants.

26. Microorganism:
    Microorganisms are tiny living organisms that cannot be seen without a microscope.
    Example: Bacteria are microorganisms.

27. Bacteria:
    Bacteria are microscopic organisms found everywhere.
    Example: Some bacteria help in digestion.

28. Virus:
    A virus is a very small organism that causes diseases.
    Example: The flu is caused by a virus.

29. Fungi:
    Fungi are organisms that do not make their own food.
    Example: Mushroom is a fungus.

30. Algae:
    Algae are simple plant-like organisms that live in water.
    Example: Seaweed is algae.

31. Plant:
    A plant is a living organism that makes its own food.
    Example: A mango tree is a plant.

32. Animal:
    An animal is a living organism that cannot make its own food.
    Example: A dog is an animal.

33. Vertebrate:
    Vertebrates are animals that have a backbone.
    Example: Fish are vertebrates.

34. Invertebrate:
    Invertebrates are animals without a backbone.
    Example: Earthworms are invertebrates.

35. Blood:
    Blood is a fluid that transports oxygen and nutrients in the body.
    Example: Blood carries oxygen to all body parts.

36. Heart:
    The heart is an organ that pumps blood throughout the body.
    Example: The human heart beats continuously.

37. Lungs:
    Lungs are organs that help in breathing.
    Example: Lungs absorb oxygen from air.

38. Digestive System:
    The digestive system helps break down food into simpler substances.
    Example: The stomach is part of the digestive system.

39. Circulatory System:
    The circulatory system helps transport blood in the body.
    Example: The heart and blood vessels form this system.

40. Nervous System:
    The nervous system controls and coordinates body activities.
    Example: The brain controls the nervous system.

41. Skeletal System:
    The skeletal system provides shape and support to the body.
    Example: Bones form the skeletal system.

42. Muscular System:
    The muscular system helps in body movement.
    Example: Muscles help us walk.

43. Respiratory System:
    The respiratory system helps in breathing.
    Example: The lungs are part of this system.

44. Excretory System:
    The excretory system removes waste from the body.
    Example: Kidneys are part of the excretory system.

45. Balanced Diet:
    A balanced diet contains all nutrients in the right amount.
    Example: A meal with rice, vegetables, and fruits is balanced.

46. Nutrients:
    Nutrients are substances needed for growth and health.
    Example: Proteins help in body growth.

47. Disease:
    A disease is a condition that makes the body unhealthy.
    Example: Malaria is a disease.

48. Communicable Disease:
    Communicable diseases spread from one person to another.
    Example: Common cold is communicable.

49. Non-communicable Disease:
    Non-communicable diseases do not spread between people.
    Example: Diabetes is non-communicable.

50. Vaccination:
    Vaccination is the process of protecting the body from diseases.
    Example: Polio drops protect children from polio.