- The cell is basic unit of life
- All organisms are made up of cells
- All cells arise from pre-existing cells: Mitosis.
Eukaryotes: One having true, membrane bound nucleus, includes all plants, animals, fungi and Protoctists.
- Plasma membrane or Cell surface membrane
Aqueous solution of ions, organic compounds, e.g. Sugar and amino acids
Includes Ribosomes, ER, Golgi body, vacuole and centrioles.
Network of microtubules, intermediate filaments and microfilaments
Found in plant cells!
- Contains Heredity material
- Essential for cell division
- Regulated protein synthesis
- Receives proteins and lipids from the ER and chemically modifies them.
- Sorts and package proteins and transport them to various cellular locations. Hence it is also known as “Post office” of the cell.
- Formation of lysosomes.
- Synthesis of new cell wall.
- Fuse with vesicles formed by endocytosis and hydrolyze material within.
- Autophagy: worn-out organelles are digested.
- Autolysis: self-digestion of cell.
- Involved in cellular respiration
- Formation of ATP
- Site for photosynthesis.
- Plants vacuole keeps it turgid.
- May contain pigments
- Contain hydrolytic enzymes.
- Act as food reserves.
- Store for waste products.
- For Osmoregulation in Paramecium
- Maintains the shape of cell
- Prevents the cell from bursting
- Provides support and mechanical strength
- Physical barrier for pathogens
- Varies in thickness from 5 nm to 10nm
- Phospholipid is the main lipid found in this membrane forming bilayer with hydrophobic tails facing inwards and hydrophilic heads facing outwards.
Two types of proteins are associated to this membrane
- Peripheral/Extrinsic protein that occurs on the surface of the phospholipid bilayer bounded to it by hydrophilic bonds
- Integral/Intrinsic protein which penetrates only part of the way into or all the way through the bilayer.
- Cell membrane also contains carbohydrates bonded to proteins or lipids forming glycoproteins or glycolipids.
- Cholesterol is found between phospholipid molecules.
- Cell membranes are asymmetric
- These are fluid structures
- Boundary between contents of a cell and external environment
- Partially permeable.
- Sense the external changes and response to them.
- Maintain structural relationship with neighboring cells.
- Enable separate compartments to be formed within the cell.
- Allow the attachment to the enzymes.