Human anatomy & physiology(मानव शरीर रचना एवं क्रिया विज्ञान) Cell : Cell, Structure and Function,

1. CELL
BY Prof. Nilachal

2. HUMAN ANATOMY & PHYSIOLOGY
(मानव शर'र रचना एवं +,या .व/ान)
These two branches of science—anatomy and physiology—provide the foundation for
understanding the body’s parts and functions.
Anatomy (a-NAT-o ̄-me ̄; ana- up; -tomy process of cutting) is the science of body
structures and the relationships among them.
physiology (fiz-e ̄-OL-o ̄-je ̄; physio- nature; -logy study of) is the science of body
functions—how the body parts work.

4. LEVELS OF
STRUCTURAL
ORGANIZATION
IN THE HUMAN
BODY.

5. HOMEOSTASIS
• 1. Homeostasis is a condition of equilibrium in the body’s internal environment
produced by the interplay of all the body’s regulatory processes.
• 2. Body fluids are dilute, watery solutions. Intracellular fluid (ICF) is inside cells,
and extracellular fluid (ECF) is outside cells. Interstitial fluid is the ECF that fills
spaces between tissue cells; plasma is the ECF within blood vessels.
• 3. Because it surrounds all body cells, interstitial fluid is called the body’s internal
environment.
• 4. Disruptions of homeostasis come from external and internal stimuli and
psychological stresses.
• 5. When disruption of homeostasis is mild and temporary, responses of body cells
quickly restore balance in the internal environment. If disruption is extreme,
regulation of homeostasis may fail.

6. BASIC ANATOMICAL TERMINOLOGY

7. DIRECTIONAL
TERMS

8. Self Practice

9. CELL
(को$शका)

10. WHAT IS CELL ?
• Cyto : "Cyto-" is derived from the Greek "kytos" meaning "hollow, as a cell or container."
• Cytology = Study of cells
• Cell is the structural and functional unit of all living organisms.
• Basic Facts in Human cell:
• Smallest cell: sperm
• Largest Cell: female ovum
• Longest Cell: neuron
• Do not regenerate: neurons don’t reproduce or regenerate
• Do regenerate: Liver

11. CELL THEORY
• Cell Theory is a collection of ideas and conclusions from many different
scientists over time that describes cell and how cells operate.
1. All known living things are made up of one or more cells.
2. All living cells arise from pre-existing cells by division.
3. The cell is the basic unit of structure and function in all living organisms.

12. CELL THEORY TIMELINE

13. UNICELLULAR ORGANISMS

14. MULTICELLULAR ORGANISMS

15. SIZE OF CELLS
• Cells vary in size
• Microscopic
• Eg. Mycoplasma; size: 0.1millimetre
• Macroscopic
• Eg. Ostrich egg; size: 18 millimetre
• Most cells are very small.

16. SIZE OF CELLS IN HUMANS

17. SHAPE OF CELLS
• Cells vary in shape
• Variation depends mainly upon
the function of cells.
• Some cells like Euglena and
Amoeba can change their
shape, but most cells have a
fixed shape.

18. STRUCTURE OF CELL
• The detailed structure of a cell has
been studied under compound
microscope and electron
microscope.
• Certain structures can be seen only
under an electron microscope.
• The structure of a cell as seen under
an electron microscope is called ultra
structure.

19. ANIMAL CELL

20. Figure: Animal cell under the microscope. Image Source: The Greatest Garden.

21. STRUCTURE OF A CELL
Threecomponentsinacell:
Plasma
Membrane
Nucleus
Cytoplasm
Cytosol
Cell Organelles
Endoplasmic
reticulum
Golgi body
Lysosomes
Vacuoles
Mitochondria
Centrosome
Cytoskeleton

23. PLASMA MEMBRANE

24. NUCLEUS

26. CYTOPLASM

27. ENDOPLASMIC RETICULUM

28. GOLGI BODY

29. LYSOSOMES

30. VACUOLES

31. MITOCHONDRIA