Cellular level of organization of human body.pptx

Cells are the basic structural and functional units found in all living organisms. Study the cellular level of organization in the human body, a key concept in biology and anatomy. This presentation examines the formation and function of cells, the fundamental building blocks of life. It covers:
Different types of human cells and their specialized functions.
Key cellular components, including the nucleus, cytoplasm, mitochondria, and cell membrane.
Processes such as cell division, metabolism, and cellular communication.
The role of stem cells and cellular differentiation in growth, development, and repair.
This presentation provides an overview of the cellular level of organization in the human body. It explains the structure and function of cells as the basic units of life, highlighting their components such as the cell membrane, nucleus, cytoplasm, and organelles (mitochondria, ribosomes, etc.).
Gain insights into how cells perform essential activities to maintain life, paving the way for understanding more advanced topics in biology.

1. Cellular level of organization Presented By: Ms Shraddha M. Parab Assistant Prof. Department of Pharmacology Yashwantrao Bhonsale College of Pharmacy, Sawantwadi

2. Contents Introduction Parts of cell Plasma membrane Cytoplasm Organelles Nucleus

3. Introduction A cell is the basic, living, structural, and functional unit of the body. Cell biology is the scientific study of cellular structure and function . Robert Hook was the first scientist who discovered Cells.

4. Parts of cell The principal parts of a cell are: The plasma membrane The cytoplasm: the cellular contents between the plasma membrane and the nucleus. The nucleus

5. Plasma membrane The plasma membrane, a flexible yet sturdy barrier that surrounds and contains the cytoplasm of a cell, is best described by using a structural model called the fluid mosaic model. According to this model, the molecular arrangement of the plasma membrane resembles an ever-moving sea of fluid lipids that contains a mosaic of many different proteins. According to this biological model , there is a lipid bilayer in which protein molecules are embedded . Two back-to-back layers made up of three types of lipid molecules — phospholipids, cholesterol, and glycolipids

6. Cytoplasm The cytoplasm has two components Cytosol : It is the fluid portion of the cytoplasm that contains water (75-90 %), ions, amino acids, proteins, lipids, ATP, and waste products. Organelles : Ribosomes Endoplasmic reticulum (smooth and rough) Golgi complex Mitochondria Nucleus

7. Ribosomes These are tiny granules composed of RNA and protein . They synthesize protein from amino acids using RNA. When this is present in free units in the cytoplasm, the ribosomes make proteins for use within the cell. Ribosomes are also found on the outer surface of the nuclear envelope and rough endoplasmic reticulum where they manufacture proteins for export from the cell.

8. Endoplasmic Reticulum It is the series of interconnecting membranous canals in the cytoplasm. There are 2 types of endoplasmic reticulum Smooth endoplasmic reticulum: Here is a lack of ribosomes Rough endoplasmic reticulum: This is studded with ribosomes that synthesize proteins .

9. Golgi Complex It consists of 3 to 20 cisternae like a stack of closely folded flattened membranous sacs . It is present in all cells but is larger in those cells that synthesize and export proteins . The proteins move from the ER to the Golgi apparatus where they are ‘packaged’ into membrane-bound vesicles called secretory granules. The vesicles are stored and when needed moved to the plasma membrane, through which the proteins are exported.

10. Lysosome Lysosomes are membrane-enclosed vesicles that form from the Golgi Complex. Inside, as many as 60 kinds of powerful digestive and hydrolytic enzymes are present that can hydrolyze large molecules such as RNA, DNA, amino acids, and proteins. Lysosomal enzymes work best at an acidic pH=5 and are inactivated at neutral pH .

11. Mitochondria This is also called the 'Power House ' of cells. They are involved in the aerobic respiration . The process by which chemical energy is made available in the cell. This energy is in the form of ATP which releases energy when the cell breaks it down.

12. Nucleus The nucleus is a spherical or oval-shaped structure that usually is the most prominent feature of a cell Every cell in the body has a nucleus, with the exception of mature RBC . Skeletal muscle and some other cells contain several nuclei. It is the larger organelle of the cell and is contained within the nuclear envelope . The nucleus contains the body's genetic material which directs all metabolic activities of the cell. This consists of 46 chromosomes , which are made from DNA.