The CellThe Cell

An internet laboratory on the An internet laboratory on the cell, created by Wendy M. cell, created by Wendy M. Rounds 5/3/00Rounds 5/3/00

The CellThe Cell

Cells are the basic unit of life.Cells are the basic unit of life. Cells carryout all the necessary Cells carryout all the necessary

functions for life such as: functions for life such as: reproduction, taking in nutrients reproduction, taking in nutrients and excreting wastes.and excreting wastes.

Cells are made up of chemicals Cells are made up of chemicals and molecules. Human cells and molecules. Human cells contain mostly water.contain mostly water.

The CellThe Cell

Cells are classified as prokaryotic Cells are classified as prokaryotic and eukaryotic.and eukaryotic.

Prokaryotic cells lack a well-defined Prokaryotic cells lack a well-defined nucleus and many organelles. nucleus and many organelles. Bacteria are prokaryotic cells. Bacteria are prokaryotic cells.

Eukaryotic cells include the protists, Eukaryotic cells include the protists, fungi, plant and animal cells. We fungi, plant and animal cells. We will study these cells during this lab.will study these cells during this lab.

The CellThe Cell

Animal CellsAnimal Cells Have centriolesHave centrioles Store glucose as Store glucose as

glycogenglycogen Do not have a cell Do not have a cell

wallwall Contain Contain

mitochondriamitochondria

Plant CellsPlant Cells Lack centriolesLack centrioles Store glucose as Store glucose as

cellulose or starchcellulose or starch Have a cell wallHave a cell wall Have large vacuolesHave large vacuoles Contain Contain

chloroplasts as well chloroplasts as well as mitochondriaas mitochondria

The CellThe Cell

Animal CellAnimal Cell Click on the cell Click on the cell

to study it in more to study it in more detaildetail

Plant CellPlant Cell Click on the cell Click on the cell

to study it in more to study it in more detaildetail

Animal CellAnimal CellClick on each organelle to learn its function. When you have Click on each organelle to learn its function. When you have finished click on the arrow button to study the plant cell.finished click on the arrow button to study the plant cell.

Plant CellPlant CellClick on each organelle to study its function. When you have Click on each organelle to study its function. When you have finished click finished click herehere to study the animal cell or to study the animal cell or here here to continue to continue this lab.this lab.

Cell ExtensionsCell Extensions

Two types of cellular extensions are cilia and Two types of cellular extensions are cilia and flagella.flagella.

Cilia are small hairlike projections which beat to Cilia are small hairlike projections which beat to move substances. The respiratory tract is lined with move substances. The respiratory tract is lined with cilia which only beat in one direction to move cilia which only beat in one direction to move substances up from the lungs. (then we swallow substances up from the lungs. (then we swallow them)them)

Flagella (flagellum is the singular) are cellular Flagella (flagellum is the singular) are cellular projections which help the cell to move. A flagellum projections which help the cell to move. A flagellum is found on sperm cells and helps them to swim to is found on sperm cells and helps them to swim to fertilize the egg.fertilize the egg.

Lab ReportLab Report

Once you have reviewed the Once you have reviewed the organelles of the animal and plant organelles of the animal and plant cells. Open the Lab Report which cells. Open the Lab Report which you downloaded from WebCT with you downloaded from WebCT with this file.this file.

NucleusNucleus

The nucleus is the The nucleus is the controller of the cell.controller of the cell.

It is surrounded by the It is surrounded by the nuclear envelope which nuclear envelope which controls what substances controls what substances may exit/enter the nucleus.may exit/enter the nucleus.

It contains DNA and the It contains DNA and the nucleolus.nucleolus.

DNA is termed the “genetic DNA is termed the “genetic blueprint” and directs all blueprint” and directs all protein synthesis.protein synthesis.

The nucleolus makes The nucleolus makes ribosomes.ribosomes.

Back

Nucleus-PlantNucleus-Plant

The nucleus is the The nucleus is the controller of the cell.controller of the cell.

It is surrounded by the It is surrounded by the nuclear envelope which nuclear envelope which controls what substances controls what substances may exit/enter the nucleus.may exit/enter the nucleus.

It contains DNA and the It contains DNA and the nucleolus.nucleolus.

DNA is termed the “genetic DNA is termed the “genetic blueprint” and directs all blueprint” and directs all protein synthesis.protein synthesis.

The nucleolus makes The nucleolus makes ribosomes.ribosomes.

Back

RibosomesRibosomes

Ribosomes are protein Ribosomes are protein factories. All protein factories. All protein synthesis occurs within synthesis occurs within the ribosome.the ribosome.

They may be fixed They may be fixed (attached to the (attached to the endoplasmic reticulum) endoplasmic reticulum) or free floating in the or free floating in the cytoplasmcytoplasm

They are composed of They are composed of rRNA and proteins.rRNA and proteins.

Free floating and Free floating and fixed:fixed:

Cell

Endoplasmic Reticulum

Back

Ribosomes-PlantRibosomes-Plant

Ribosomes are protein Ribosomes are protein factories. All protein factories. All protein synthesis occurs within synthesis occurs within the ribosome.the ribosome.

They may be fixed They may be fixed (attached to the (attached to the endoplasmic reticulum) endoplasmic reticulum) or free floating in the or free floating in the cytoplasmcytoplasm

They are composed of They are composed of rRNA and proteins.rRNA and proteins.

Free floating and Free floating and fixed:fixed:

Cell

Endoplasmic Reticulum

Back

Endoplasmic ReticulumEndoplasmic Reticulum

The endoplasmic reticulum The endoplasmic reticulum or ER is a network of or ER is a network of channels which assist in the channels which assist in the synthesis and transport of synthesis and transport of cellular products.cellular products.

There are two types:There are two types: smooth ER which is smooth ER which is

involved in the synthesis of involved in the synthesis of lipid products such as lipid products such as steroid hormones.steroid hormones.

Rough ER which has Rough ER which has ribosomes attached to it & ribosomes attached to it & is involved in protein is involved in protein synthesis.synthesis.

Back

Endoplasmic Reticulum-Endoplasmic Reticulum-PlantPlant

The endoplasmic reticulum The endoplasmic reticulum or ER is a network of or ER is a network of channels which assist in the channels which assist in the synthesis and transport of synthesis and transport of cellular products.cellular products.

There are two types:There are two types: smooth ER which is smooth ER which is

involved in the synthesis of involved in the synthesis of lipid products such as lipid products such as steroid hormones.steroid hormones.

Rough ER which has Rough ER which has ribosomes attached to it & ribosomes attached to it & is involved in protein is involved in protein synthesis.synthesis.

Back

Golgi ApparatusGolgi Apparatus

This organelle consists of This organelle consists of tubular channels which tubular channels which function to assemble, and function to assemble, and check proteins coming from check proteins coming from the rough ER.the rough ER.

The golgi apparatus also The golgi apparatus also ensures that the completed ensures that the completed proteins go to the proteins go to the

appropriate area of theappropriate area of the cell. (that proteins for the cell. (that proteins for the cell membrane get to the cell membrane get to the membrane, proteins membrane, proteins hormones exit the cell etc.)hormones exit the cell etc.)

Back

Golgi Apparatus-PlantGolgi Apparatus-Plant

This organelle consists of This organelle consists of tubular channels which tubular channels which function to assemble, and function to assemble, and check proteins coming from check proteins coming from the rough ER.the rough ER.

The golgi apparatus also The golgi apparatus also ensures that the completed ensures that the completed proteins go to the proteins go to the

appropriate area of theappropriate area of the cell. (that proteins for the cell. (that proteins for the cell membrane get to the cell membrane get to the membrane, proteins membrane, proteins hormones exit the cell etc.)hormones exit the cell etc.)

Back

Lysosomes Lysosomes

Lysosomes contain powerful Lysosomes contain powerful digestive enzymes which digestive enzymes which break apart anything that break apart anything that gets inside it. gets inside it.

They are important in They are important in protection (splitting bacteria) protection (splitting bacteria) as well as, old organelles. as well as, old organelles.

Lysosomes are able to Lysosomes are able to release the end products for release the end products for reuse in the cell.reuse in the cell.

It is important that the It is important that the lysosome doesn’t rupture or lysosome doesn’t rupture or the enzymes would digest the enzymes would digest the cell.the cell.

Back

MitochondriaMitochondria

Mitochondria are the Mitochondria are the “powerhouses” of “powerhouses” of the cell.the cell.

They are responsible They are responsible for carrying out for carrying out aerobic cellular aerobic cellular respiration.respiration.

This process forms This process forms ATP from the food ATP from the food we eat and requires we eat and requires oxygen.oxygen.Back

Mitochondria-PlantMitochondria-Plant

Mitochondria are the Mitochondria are the “powerhouses” of “powerhouses” of the cell.the cell.

They are responsible They are responsible for carrying out for carrying out aerobic cellular aerobic cellular respiration.respiration.

This process forms This process forms ATP from the food ATP from the food we eat and requires we eat and requires oxygen.oxygen.Back

CytoskeletonCytoskeleton

The cytoskeleton The cytoskeleton functions as the “muscles functions as the “muscles and bones “of the cell.and bones “of the cell.

It consists of:It consists of: Microfilaments: which Microfilaments: which

help the cell to move help the cell to move (muscle contraction)(muscle contraction)

Intermediate Filaments: Intermediate Filaments: which prevent the cell which prevent the cell from being pulled apart.from being pulled apart.

Microtubules: function in Microtubules: function in maintaining the cell maintaining the cell shape.shape.Back

Cell WallCell Wall

Only found in plant cellsOnly found in plant cells Surrounds cell membraneSurrounds cell membrane Composed of lignin and celluloseComposed of lignin and cellulose Function to strengthen and protect Function to strengthen and protect

plant cells.plant cells.

Back

Central VacuoleCentral Vacuole

Large organelleLarge organelle Comsists of mostly water, plant Comsists of mostly water, plant

pigments, and toxins.pigments, and toxins. Functions for storage of nutrients Functions for storage of nutrients

and pigments, and retains waste and pigments, and retains waste products.products.

The pigments which give a flower The pigments which give a flower its color are stored in the vacuole.its color are stored in the vacuole.

Back

ChloroplastsChloroplasts

Contain green Contain green pigment termed pigment termed chlorophyll.chlorophyll.

Function in Function in photosynthesisphotosynthesis

Back