Human cells contain various organelles that carry out essential functions. The basic components of a cell include the cell membrane, cytoplasm, nucleus, and organelles like mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, and cytoskeleton. The cell membrane forms the boundary of the cell and regulates what enters and exits. The nucleus contains genetic material and influences cell activities. Mitochondria generate energy for cell processes through ATP production. Other organelles are involved in protein synthesis, modification and transport, waste breakdown, and maintaining cell structure.

1. HUMAN CELL
ANATOMY
ANANYA GIRISH BABU
LECTURE

2. CONTENT
• What is cell
• Function
• Components
• Anatomy
• Organelles of cell

3. CELL
•Cell is a basic structural , functional and biological unit of all the living organism.
•CELL in biology, the basic membrane-bound unit that contains the fundamental molecules of life and of which
all living things are composed
•It is a minute jelly like mass of protoplasm containing a nucleus held together by a cell membrane
•Study of cell is called cytology
•Robert Hook who first coined the term cell in 1665
•Range in size : 50-150 pm in diameter.
•>Human body is composed of 75 - 100 trillions of cells ( age dependent).

4. FUNCTIONS OF CELL
• IRRITABILTY – the cell has the ability to detect and respond the change in its environment
• NUTRITION – they absorb fluids and dissolve substance directly through cell membrane
• RESPIRATION - they use oxygen combined with food to form carbon dioxide and water
• GROWTH AND REPRODUCTION
• MOVEMENT – muscle cell
• ION TRANSPORT – cells of kidney, duct of salivary glands

6. STRUCTURE OF CELL
Cell is made up of following structure
1. Cell membrane or plasma membrane
2. Nucleus
3. Cytoplasm
4. Endoplasmic reticum
5. Mitochondria
6. Ribosome
7. Golgi apparatus
8. Lysosomes & Peroxisome
9. Centrosome
10. cytoskeleton
Cell organelles are small cellular
structure which shows specific
function

7. Cell membrane/ Plasma membrane/
plasmalemma
• It is the protective sheet of the cell membrane which is very thin, flexible and living membrane
• Possesses fine pores consist of semi permeable made up of lipoproteins
• It is a semipermeable membrane which helps to maintain shape of the cell
• It is made up of protein, lipids and a little amount of carbohydrates
COMPOSITION – protein, Phospholipids, Cholesterol, Other lipids, Carbohydrates

8. Phospholipids bilayer with protein molecule embedded, phospholipids –
head – electrically charged- hydrophilic – on outer surface of membrane
Tail – no charge – hydrophobic , towards middle od the membrane
FUNCTION
• Protective – it is the outermost boundary of cell
• Digestion – it takes food materials
• Maintain integrity to cell
• Excretion – it excrete waste products
• Transportation across cell membrane

9. CYTOPLASM
• It is the cellular material between the plasma membrane and the
nucleus
• It is the part outside the nucleus which contain organelles and
also a nucleus
• It is a fluid that fills a cell and the cytoplasm has many different
molecules dissolved in solution, fatty acid, sugar, amino acid,
and waste products
• Formed of 80% of water
• Contents – cytosol – clear liquid portion and other structures
are organelles and inclusion bodies, cytoskeleton

10. Mitochondria
• Power house of cell
• Double membrane bounded
• Sausage shaped structure in cytoplasm
• Converts oxygen and nutrients into adenosine triphosphate(ATP)-provide energy for various biochemical
processes in the body
• Mitochondria contains outer and inner membrane
1. The outer layer which is smooth
2. An inner layer folded into sheet of tubules called cristae
• Both these cavities are enclosed a central cavity called matrix
• Mitochondria are made up of protein, phospholipids and RNA [they also contain some important
enzymes ]
• They are metabolically active cells [ muscle cells , liver cells have more mitochondria]

12. Endoplasmic reticulum
• The Endoplasmic reticulum is the inter connected network of tubular and
microsomal vesicular structure in the cytoplasm of the cell
• The endoplasmic reticulum (ER) is a large, dynamic structure that serves
many roles in the cell including calcium storage, protein synthesis and
lipid metabolism. The diverse functions of the ER are performed by
distinct domains; consisting of tubules, sheets and the nuclear envelope.
• The ER is the largest organelle in the cell and is a major site of protein
synthesis and transport, protein folding, lipid and steroid synthesis,
carbohydrate metabolism and calcium storage
They are 2 types
1. Smooth endoplasmic reticulum
2. Rough endoplasmic reticulum –

13. Smooth endoplasmic reticulum
• The smooth endoplasmic reticulum functions in
many metabolic processes.[ change food into
energy]
• It synthesizes lipids, phospholipids as in plasma
membranes, and steroids. Cells that secrete these
products, such as cells of the testes, ovaries, and
skin oil glands, have an excess of smooth
endoplasmic reticulum.
• The smooth endoplasmic reticulum also carries out
the metabolism of carbohydrates and steroids. In
muscle cells, the smooth endoplasmic reticulum
regulates calcium ion storage.
• Develops from Rough Endoplasmic Reticulum.
Rough endoplasmic reticulum
• it is the part of endoplasmic reticulum to which
granular ribosomes are attached . This part is called
granular ER. It is concerned with protein synthesis
• It possesses ribosomes attached to its membrane.
• It might develop from the nuclear envelope
• The RER is also located near the Golgi apparatus,
which transports, modifies, and packages proteins
for delivery to targeted destinations. Many proteins
that are synthesized in the RER are packaged into
vesicles and transported to the Golgi apparatus.

14. RIBOSOMES
• They are tiny granule composed of RNA and protein found throughout the cell and responsible for
making enzymes and other protein components
• They are found on the outer surface of RER
• And they contains 65% RNA and 35% protein
• Produce proteins from amino acids during a process called protein synthesis or translation. The
process of protein synthesis is a primary function, which is performed by all living cells
• They synthesis protein from amino acids

16. Golgi apparatus
• Consist of stacks of closely folded flattened membrane set
• It consists of flattened membrane disc called saccule, a typical Golgi apparatus consists of five
saccules
• They lies near the nucleus and shows micro vesicles [ secretory glands ] on the surface
• They help in process of receiving and storing of secretory products [ protein]
• It is present in all cells but is larger in those that synthesize and export proteins
• It is cup like shape structure and contain vesicles
• A Golgi body, also known as a Golgi apparatus, is a cell organelle that helps process and package
proteins and lipid molecules, especially proteins destined to be exported from the cell.

18. LYSOSOMES
• They are membrane bounded bodies, contain various hydrolytic enzymes like acid phosphate
• They are responsible for intracellular digestive process an in the breakdown of material ingested by
them
• They are large irregular structure surrounded by unit membrane and are found in the cytoplasm
• A lysosome is a membrane-bound cell organelle that contains digestive enzymes. Lysosomes are
involved with various cell processes. They break down excess or worn-out cell parts. They may be
used to destroy invading viruses and bacteria. If the cell is damaged beyond repair, lysosomes can
help it to self-destruct in a process called programmed cell death
• They are known as suicidal bag

20. Nucleus
• Large oval body near the center of the cell
• The control center for all activity
• Nucleus is found in all cells except mature erythrocytes [ RBC] and platelets
• The shape is normally rounded and placed centrally
• Nucleus contain genetic material and influences the metabolic activities of cell
• Normally cells have one nucleus but some cells like osteoclast, skeletal muscle have 2 or more
nuclei
• Nucleus id surrounded by a nuclear membrane which the membrane have many pores called
nuclear pores which the substances can transport to the cytoplasm
• Cytoplasm of nucleus is nucleoplasm contain chromatin material [ gene carrier ] and nucleolus
which is rich in RNA and concerned with protein synthesis

22. Cytoskeletons
• The network of protein filaments and microtubules in the cytoplasm that controls cells shape and
maintain intracellular organization and is involved in cell movement
Microfilaments They are small protein fibers
Provide structural support
Maintain the shape of cell
Microtubules These are large contractile protein fibers
They are involved in the movement off
organelles within the cell
Chromosomes during cell division
Centrosomes Important role in cell division
They are cylindrical in structure
composed of small microtubules

24. Thank you….