Cell: The Unit Of Life

www.wikipedia.com

www.google.com

www.nerdiscience.com

www.yahooanswers.com

Vinay Vilas Patil

A std 9th Project

Cell: The Unit Of Life

What is cell??????????

Cell is a structural and functional unit of life.

Robert Hooke – first to see and identify cork “cells.”

Cell Theory:1. All living things are composed of cells.2. Cells are the basic units of structure

and function in living things.3. New cells are produced from existing

cells.

Schleiden SchwannVirchow

1.Smooth Muscle cell.2.Ovum.3.Ephithelial cells.4.Nerve cell.5.Fat cell.6.RBCs.7.Spirogyra.8.Sperm.9.Amoeba.10.Bacteria.

Smooth muscle cell is an involuntary non-striated muscle

An ovum (plural ova, from the Latin word Ovum meaning egg or egg cell) is a haploid female reproductive cell or gamete.

Epithelia are formed of cells that line the cavities in the body and also cover flat surfaces.

A neuron (also known as a neuron or nerve cell) is an electrically excitable cell that processes and transmits information by electrical and chemical signaling.

Adipocytes, also known as lipocytes and fat cells, are the cells that primarily compose adipose tissue, specialized in storing energy as fat.

Red blood cells (also referred to as erythrocytes) are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen (O2) to the body tissues via the blood flow through the circulatory system.

Spirogyra is a genus of filamentous green algae of the order zygnematales named for the helical or spiral arrangement of the chloroplasts that is diagnostic of the genus.

The term sperm is derived from the Greek word sperma (meaning "seed") and refers to the male reproductive cells.

Amoeba (sometimes amœba or ameba, plural amoebae) is a genus of Protoza.

Bacteria are large domain of single celled prokaryote microorganisms.

The basic unit of structure and function in nearly all plants. Although plant cells are variously modified in structure and function, they have many common features. The most distinctive feature of all plant cells is the rigid cell wall, which is absent in animal cells.

Animal cells are typical of the eukaryotic cell, enclosed by a plasma membrane and containing a membrane-bound nucleus and organelles. Unlike the eukaryotic cells of plants and fungi, animal cells do not have a cell wall.

Plant and animal cells are composed of the same fundamental constituents—nucleic acids, proteins, carbohydrates, lipids, and various inorganic substances—and are organized in the same fundamental manner. A characteristic of their organization is the presence of unit membranes composed of phospholipids and associated proteins and in some instances nucleic acids.

Nucleus – large membrane-enclosed structure that contains the cell’s genetic information.

Prokaryotes – cells that do not contain nuclei. (Bacteria)

Eukaryotes – cells that contain nuclei. (All other organisms)

Organelles – structures in a cell that act like “little organs.”

Cytoplasm – the jelly-like fluid where the organelles “float.”

1.Inside the Nucleus2.Ribosomes.3.Endoplasmic Reticulum (ER)4.Golgi Apparatus.5.Lysosomes.6. Vacuoles7.Mitochondria.8.Chloroplast.9.Cytoskeleton.10.Cell Boundaries.11.Cell Membrane.

Nuclear Envelope – membrane that surrounds the nucleus.

Chromatin – consists of DNA wrapped around proteins. “Ball of string”

Chromosomes – condensed string-like structure that forms from DNA just before the cell divides.

Nucleolus – structure within the nucleus that makes ribosome's.

Nuclear Envelope

Chromatin

Nucleolus

Ribosomes – made of RNA and protein. Make Proteins!

Ribosome

Endoplasmic reticulum – internal membrane system of the cell. Lipids, proteins, and other

products are made here. Rough ER – has ribosomes Smooth ER – no ribosomes

Rough ER

Smooth ER

Golgi Apparatus – modifies, sorts, and packages proteins.

Golgi Apparatus

Lysosomes – small organelles filled with enzymes. Digest molecules to be used by the cell.

Vacuoles – store materials.

Vacuoles

Mitochondria – organelle that converts chemical energy stored in food into compounds that are more convenient for the cell to use. “Powerhouse of the Cell!”

Mitochondria

7-2

Chloroplasts – organelles that capture energy from sunlight and convert it into chemical energy. (Photosynthesis) Found only in plants.

7-2

Chloroplast

7-2

Cytoskeleton – helps cell to maintain shape, move, and move organelles.

Centrioles – help organize cell division. Not found in plants.

7-2

Cell membrane – thin, flexible membrane that surrounds the cell.

Cell walls – rigid layer around the membrane found only in bacteria, fungi and plants.

Controls what enters/leaves cell, provides support/protection.

Lipid Bilayer – double-layered sheet of phospholipids.

Two layers!

Diffusion – movement of particles from an area of high to low concentration.

Osmosis – the diffusion of water through a selectively permeable membrane. Water will move into/out of

a cell to equalize concentrations.

Cell

90% H2O10% NaCl

90% H2O10% NaCl

Concentrations areequal, so no netmovement of water!

Cell

90% H2O10% NaCl

80% H2O20% NaCl

Concentration ofwater is greater inthe cell than out, sowater will move out!

Cell

80% H2O20% NaCl

90% H2O10% NaCl

Concentration ofwater is greateroutside the cell than in, so water will move In!

Facilitated diffusion – when the plasma membrane “helps” particles pass through protein channels. No energy used.

Active transport – when the plasma membrane uses energy to move particles against a concentration gradient. Uses Transport Proteins

Tissues

Organs

Organ System

Organism

Cells

Thanks for watching