PORTFOLIOof BIOLOGICAL

CELLBY LEKSHMI

Topic:

BIOLOGICAL CELLOBJECTIVES HISTORY OF CELLCELL STRUCTURE PROKARYOTIC CELL EUKARYOTIC CELL

HISTORY OF CELL First Cells Seen in Cork

The cell was first discovered and named by Robert Hooke in 1665 but it was a dead cell.

The first man to witness a live cell under a microscope was Anton van Leeuwenhoek, who in 1674 described the algae Spirogyra. Van Leeuwenhoek probably also saw bacteria

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Formulation of the Cell Theory

1. The cell is the unit of structure, physiology, and organization in living things.2. The cell retains a dual existence as a distinct entity and a building block in the construction of organisms.3. Cells form by free-cell formation, similar to the formation of crystals (spontaneous generation).

Modern Cell Theory

1. All known living things are made up of cells.2. The cell is structural & functional unit of all living things.3.All cells come from pre-existing cells by division. (Spontaneous Generation does not occur).4.Cells contains hereditary information which is passed from cell to cell during cell division.5.All cells are basically the same in chemical composition.6.All energy flow (metabolism & biochemistry) of life occurs within cells.

Cell StructureTwo types of cells

1. PROKARYOTIC CELL2. EUKARYOTIC CELL

PROKARYOTIC CELL

EUKARYOTIC CELL

Subcellular components

All cells, whether prokaryotic or eukaryotic, have a membranethat envelops the cell, regulates what moves in and out(selectively permeable), and maintains the electric potential ofthe cell. Inside the membrane, a salty cytoplasm takes up most ofthe cell's volume. All cells (except red blood cells which lack a cellnucleus and most organelles to accommodate maximum spacefor hemoglobin) possess DNA, the hereditary material of genes,and RNA, containing the information necessary to build variousproteins such as enzymes, the cell's primary machinery. There arealso other kinds of biomolecules in cells. This article lists theseprimary components of the cell, then briefly describes theirfunction.

Organelles

Organelles are parts of the cell which are adapted and/orspecialized for carrying out one or more vital functions,analogous to the organs of the human body (such as the heart,lung, and kidney, with each organ performing a differentfunction). Both eukaryotic and prokaryotic cells have organelles,but prokaryotic organelles are generally simpler and are notmembrane-bound.

There are several types of organelles in a cell. Some (such as thenucleus and golgi apparatus) are typically solitary, while others(such as mitochondria, chloroplasts, peroxisomes and lysosomes)can be numerous (hundreds to thousands). The cytosol is thegelatinous fluid that fills the cell and surrounds the organelles.

THANK YOUBY LEKSHMI

PORTFOLIOof BIOLOGICAL CELLTopic:BIOLOGICAL CELLHISTORY OF CELLSlide Number 4Cell StructurePROKARYOTIC CELLEUKARYOTIC CELLSlide Number 8Slide Number 9THANK YOU