General Biology

Cell Theory:

Cell:

• Cell is the basic structural and functional unit of all living organism
• Smallest unit of life and can replicate independently
• The study of cell is called Cell Biology
• Vary from “single cell”(Bacteria) to “multicellular” Structures(Tissues,organs) and Organisms (Animals and plants)
• Discovered by Robert Hooke in 1665

Cell Theory:

1. Cell is the basic unit of life
2. All living things are made of cells
3. Cells came from pre-existing cells

Modern Cell Theory:

• Cell contains DNA
• All cells are the same in chemical composition and metabolic activities
• All basic chemical and physiological functions are carried out inside the cells
• Cell activity depends on the activities of sub-cellular structures within the cell

Scientists:

Anton Van Leeuwenheok

• Invented the first “handheld” microscope
• Dutch scientist who was the first to see bacteria and protists
• Coined the term “animalcules”

Robert Hooke

• Coined the term “cells”

Matthias Schleiden

• A german botanist that concluded that all plant tissues are composed of cells and that an embryonic plant arose from a single cell.

Theodor Schwann

• A german biologist that said that the cell is the basic unit of life

Rudolph Virchow

• German Scientist who discovered that all cells came from pre-existing cells

Cell Structure:

Characteristics of all cells:

• A surrounding membrane
• Protoplasm
• Organelles
• Control center with DNA

Unicellular Organisms

• An organism that is made up of only one cell
• Examples of this type of cell are Euglena, Paramecium & Yeast

Multicellular Organisms

• An organism that is made up of more than one cell
• Examples of this type of cell are Plants, Animals & Fungus

Animal Cell

• Generally small in size, cell wall and plastids are absent, vacuoles are smaller in size and less in number, centrioles are present

Plant Cell

• Generally large in size, cell wall and plastids are present, vacuoles are larger in size and more in number, centrioles are absent

Parts of a cell:

Organelle

A membrane-bound structure that carries out specific activities for the cell

Plasma membrane

Contains cell contents

Ribosomes

Sites of protein synthesis

Membrane Proteins

Channels or transport

Receptors

Cell Wall

Surrounds plasma membrane

Found in plants, fungi & many protists

Cytoplasm

Viscous Fluid containing organelle

Cytoskeleton

Filaments and fibers

Cilia & Flagella

Provides motility

Centrioles

Pairs of microtubular structures and also plays a role in cell division

Membranous Organelles

Functional components within cytoplasm and are also bound by membranes

Nucleus

Control center of the cell

Nuclear Envelope

seperates the nucleus from the rest of the cell

DNA

hereditary material

Nucleolus

Forms ribosomes

Endoplastic Reticulum

Helps move substances within the cell

Rough endoplastic reticulum

ribosomes attached to the surface and manufactures proteins

Smooth endoplastic reticulum

No attached ribosomes and has enzymes that help build molecules

Golgi Body

formed by 5-8 membranous sacs and modifies,sorts and packs materials synthesized in the cell

Lysosomes

Contains digestive enzymes and aids in cell renewal

Vacuoles

Membrane bound storage sacs

Bacteria-like organelle

Mitochondria

has their own dna and is bound by double membrane. releases energy(ATP)

Chloroplast

Solar energy capturing organelle

Cell types

Prokaryotic

First cell type on earth and is the cell type of the bacteria and archaea

no membrane bound nucleus

Eukaryotic

Nucleous bound by membrane

posesses many organelles

Animal cells and tissue video nalang masyado mahaba ppt ni sir

https://www.youtube.com/watch?v=fNQ92ZGWpOA&list=PLmdFyQYShrjfFwBor3IVoTy5JspWHrFdH

https://www.youtube.com/watch?v=UlINGF9MnNA