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Wednesday, September 17, 2014

1styear BIOLOGY Notes Chapter-1

Chapter-1
INTRODUCTION

DEFINITION OF BIOLOGY
Biology is the study of living organisms. It is derived from Greek words. Bios – life Logos – study.


CLASSIFICATION OF LIVING ORGANIZATION
According to the modern classification given by R.H.Whittaker in 1969, living organisms are divided into five major kingdoms, which are:

KINGDOM MONERA
It includes all prokaryotes, unicellular organisms. For example Bacteria and Cyan bacteria.

KINGDOM PROTOCTISTA(PROTISTA)
It includes unicellular Eukaryotic organisms, which are in between plants and animals. e.g. Chlamydomonas, Euglena, Paramecium. etc.

1. KINGDOM FUNGI
It includes non-chlorophyllus multi-cellular, thallophytic organisms having cell wall. For example all types of fungi, unicellular to multi-cellular like Mushrooms and Yeast etc.

2. KINGDOM PLANTAE
It includes all chlorophyllus multi-cellular Eukaryotic living organisms having cellulose cell wall. For example apple, red wood etc.

3. KINGDOM ANIMALIA
It includes all Eukaryotic multi-cellular, non-chlorophyllus organisms having no cell wall. For example Hydra, Earthworm, Human Beings etc.

EUKARYOTIC ORGANISMS
Those organisms, which have true membranous structure in their cells, like mitochondria, golgi bodies, endoplasmic reticulum. e.g. All plants, Higher animals.

PROKARYOTES
Those living organisms, which do not have true membranous structure in their cells. e.g. Bacteria, Blue green algae.

PHYLETIC LINEAGE
All living organisms of today belong to a common ancestor and each specie of organism arranged no ancestor to descendent order with rest of the group evolved from one that immediately preceded.

BRANCHES OF BIOLOGY
1. MOLECULAR BIOLOGY
It is a recent branch of biological science that deals with the structure and function of the molecules that form structure of cell and organelles that take part in the biological processes of a living organism (Nucleic acid – Protein molecule)

2. MICRO BIOLOGY
It deals with the study of micro-organisms (viruses, bacteria, protozoan etc)

3. ENVIRONMENTAL BIOLOGY
It deals with the study of environment and its effect on organisms.

4. MARINE BIOLOGY
It deals with the study of organisms inhabiting the sea an ocean, and the physical and chemical characteristics of their environment.

5. FRESH WATER BIOLOGY
It deals with the life dwelling in fresh waters, physical and chemical characteristics of fresh water bodies affecting it.

6. PARASITOLOGY
It deals with the study of parasitic organisms, their life cycles, mode of transmission and interaction with their hosts.

7. HUMAN BIOLOGY
The branch of biology deals with all biological aspects of man regarding evolution, anatomy physiology, health, inheritance etc.

8. SOCIAL BIOLOGY
Social biology is concerned with the social interactions with in a population of a given species, especially in human beings focuses on such issue as whether certain behavior are inherited or culturally induced.

9. BIOTECHNOLOGY
This is a very recent branch introduce in biological sciences. It deals with the use of data and techniques of engineering and technology for the study and solution of problems concerning living organisms particularly the human beings.

BIOLOGICAL METHOD
In order to solve the biological problems (any animal or plant disease or environmental hazard), following steps are necessary.

1. HYPOTHESIS
An educated guess or fact regarding the biological problem.

INDUCTIVE REASONING
Isolated facts to reach a general idea that explain the biological problem.

DEDUCTIVE REASONING
Accurate experimentation, true conclusions or results regarding the biological problems.

2. OBSERVATION/EXPERIMENTS
The given hypothesis is checked with the help of observation and experiments and then on the basis of it a theory or rule is established.

3. THEORY
If observations and experiments come true then hypothesis is taken true, other wise it is rejected. Only on the basis of true hypothesis a theory is established.

4. LAW/PRINCIPLE
When theory is proved to be true under all tested circumstances then it is accepted as a law.

MALARIA
• Malaria means disease cause by bad air.
• Actual Causative agent is plasmodium (Vector Female, Anopheles Mosquito)
• Leveran first discover plasmodium in human R.B.C.
• Ronald Ross discovered plasmodium in the stomach of female Anopheles Mosquito.
• Grassi discover the complete life cycle of Plasmodium in human being and mosquito.

ANTIBIOTICS
Substances or chemicals, which are required in small quantity to inhibit the growth of Microorganisms. The first antibiotic was penicillin discovered by Fleming. Other examples are: Erythocin, Rythocin, Gentamycin, Ampicillin etc.

CHEMOTHERAPY
Treatment with drug or chemical.

RADIOTHERAPY
Treatment with radiations, like a, ß, ? or X-rays.

HYDROPONICS
It is the science of terrestrial plants growing in aerated solutions (add CO2 under pressure, in any liquid also known as aerated water). This technique is also known as soil less or water culture.
ADVANTAGES
1. Control weeds and soil disease problems.
2. Area required for cultivation is minimum.
3. Can be applied on any part of the world.
4. Main purpose is to fulfill the food requirements of rapidly increasing world population.

CLONING
Production of duplicate copies of genetic material, cells or entire multicellular living organisms, occurring naturally in plants or animals. Duplicate copies are known as clones.

NATURAL CLONING
• Identical twin, triplet in humans.
• A***ual reproduction in plants and animal.
• Regeneration and wound healing.
• Growth of tumor cells or cancers.

ARTIFICIAL CLONING
• Cloning of human cells such as liver cells, skin cells, blood cells are quite helpful to develop human organs in laboratories.
• There are also enormous advantages of cloning in the field of medicine and agriculture. Examples are vegetative reproduction of fruits and nuts by grafting.
• Artificial cloning is also used for treating disease, production of medically significant substances such as Insulin, growth hormones, interferon and anti-thrombin etc.

LEVEL OF BIOLOGICAL ORGANIZATION
Life is built on chemical foundation and the life of all living organisms emerges on the level of cell. The foundation of cell is based on elements. Atoms of different elements unite to form molecules. Living organism usually form extremely large and complex molecules by living matter which is present in their bodies. The molecules of living organisms are mostly composed of carbon and provide building blocks of living matter. Mostly living matter of an organism is composed of organic molecules along with inorganic compounds (minerals) are also associated for e.g. Human blood. Simple organic molecules present in living organisms are sugar, glycerol and fatty acids, amino acids, purine and pyramidines. Similar types of cells form-tissues, similar tissues form organs, different organs coordinating with each other form system and different systems combine to form a living organism.
Cell →Tissues → organs →System → An Individual
Biological organization can be divided into the following levels:

SUB-ATOMIC PARTICLES
“Particles that make up an atom are called sub-atomic particles”.
For e.g. electron, proton and Neutron.

ATOM
“The smallest particle of an element that retains the property of that element”.
For example: Hydrogen, carbon and oxygen etc.

MOLECULE
“The combination of similar and different atoms are called molecules”.
For example Hydrogen and oxygen combines to form water molecules.

ORGANELLE
“A structure with in a cell that performs a specific function”.
For example: Mitochondria, chloroplast etc.

CELL
“The smallest structural and functional unit of life”.
For example: A nerve cell

TISSUE
“A group of similar cells that performs a specific function”.
For example: Nervous tissue.

ORGAN
"A structure with in an organism usually compose of several tissue types that forms a functional unit”.
For example: The brain

ORGAN SYSTEM
“Two or more organs working together in the execution of a specific bodily function”.
For example: The nervous system.

MULTICELLULAR ORGANISM
“An individual living thing composed of many cells are called Multicellular organisms”.
For example: Pronghom antelope.

SPECIE
“A group of very similar inter breeding organisms constitutes a species”.
For example Herd of pronghom antelope.

POPULATION
"Members of same species inhabiting the same area are considered as population”.
For example: Herd of pronghom antelope.

COMMUNITY
“Population of several species living and interacting in the same area form a community”.
For example: Snake, antelope and hawk.

ECO-SYSTEM
“A community with its environment including land, water and atmosphere, constitute an eco-system”.

BIOSPHERE
“The part of earth inhibited by living organisms, both living and non-living components."

Tuesday, September 16, 2014

How to Block Websites

Block a Website on Your PC

1. Open Windows Explorer and navigate to C:\Windows\System32\drivers\etc. If Windows is not installed on C:, substitute the appropriate drive letter.
2. Double-click hosts, and select Notepad when Windows prompts you to choose a program. If you don't get the prompt, or if the hosts file opens in another program, open Notepad (Start, All Programs, Accessories, Notepad), and then navigate to hosts by clicking File, Open within Notepad.
How to Block a Website on Your PC
3. Place the cursor at the end of the last line, which will say something such as '127.0.0.1 localhost' or '::1 localhost'. Press Enter to create a new line.
4. Type 127.0.0.1, tap the spacebar once, and then type the address of a website you want to block. For example, to block all traffic from YouTube, type127.0.0.1 www.youtube.com on this line.
5. Continue to add the websites you wish to block, each prefaced with 127.0.0.1 and a space.
How to Block a Website on Your PC
6. Click File, Save to commit to your changes. Dismiss any warnings from antimalware software, which may be triggered by your editing of the hosts file.
7. Close any open browser windows, and then reopen a browser to test your edits. The blocked sites should not display in any browser.

Selectively Block a Website Based on User or Time of Day

If blocking a site from all users at all times is overkill for your situation and you want more control, try using your router’s Web interface to block a website selectively.
1. Open a browser and enter your router’s IP address into the address bar. Refer to your router’s documentation for the IP address, or, if you don’t immediately know it, try a common address such as http://192.168.1.1, http://192.168.0.1, or http://192.168.2.1.
2. Enter your username and password. If you haven’t changed the username and password, and you don’t know the defaults, visit Port Forward’s Default Router Passwords page to find them.
3. Browse to the section where you can block websites, computers, and access during certain times of day. Router interfaces vary, but look for a section with a name such as 'Access Restrictions'.
4. Enter the details of the content and the users you’d like to restrict, and save your changes. Your router’s paper or electronic documentation should provide full instructions.
Remember to exercise caution when editing your hosts text file, and always make sure to back up files before you edit them.

Blocking a website on a router

Access pointMost home networks today have a network routerfor sharing an Internet connection between multiple devices. In addition to routing the network information between devices, the router can also block websites. We recommend blocking a website through a router because it can be password protected to prevent the block from being bypassed and because it will block a website on all devices. This means if you were trying to block Facebook from your children it will be blocked on the computer as well as any cell phone or tablet connected to your home network.
To block a website on a router connect to the home network router, typically this is done by opening a browser and visiting the default router address: http://192.168.1.1
If this address does not work or you're having trouble accessing your router setup visit the link below.
After connecting to the router, block a website through one of the below features. Unfortunately, every router setup is different so you'll need to find one of the below settings for your manufacturer of the router. Generally one of these options will be available under a "Security", "Parental control", "Firewall" tab or button.
  • URL Filter - Some routers may have a URL filter section, which allows you to enter the URL for each website you want to block.
  • Parental controls - New and more advanced routers have a section dedicated to parental controls, which gives you not only the option to block websites but also specify the times the Internet can be accessed.
  • Firewall - Finally, if neither of the above options is available the router should offer some type of filtering through the Firewall router settings.

Block a website using Family safety

Note: Blocking a site using these steps only blocks the website on one computer. Any other computer, phone, or tablet connected to your computer will be able to access the site you're blocking.
The new versions of Windows include a new Windows Family Safety feature that allows parents to setup computer usage rules and includes the ability to only allow certain websites or block websites. If you're running Windows 7 or Windows 8, open Family Safety from either the Windows Start Menu or Start Screen by typing "family" and then clicking on the Family Safety shortcut that should appear.
When open you'll have a screen that resembles the example below which gives you access to web filtering, time limits, logs, as well as the type of games that can be played.
Windows Family Safety

Blocking a website in Windows

Note: Blocking a site using these steps only blocks the website on one computer. Any other computer, phone, or tablet connected to your computer will be able to access the site you're blocking.
A website can be blocked on any Windows computer by editing the hosts file, in Windows this file is referred to as the lmhost file.
Locate the hosts file in Windows Explorer. For Windows XP and up, it will be located in the directory C:\WINDOWS\system32\drivers\etc\. In Windows 2000/NT, C:\WINNT\system32\drivers\etc\. In Windows 98 and ME, C:\WINDOWS\.
Navigate to the proper directory using Windows Explorer. Double-click the hosts file. Choose Notepad from the list of programs to open the file and edit it in Notepad.
Find the line below:
127.0.0.1 localhost
Right underneath it, add the following lines (replacing badsite.com with the site you want to block):
127.0.0.1 badsite.com
127.0.0.1 www.badsite.com
Click on the File menu and click Save. Close the file. The site should be blocked in all web browsers and now instead of trying to access that site the computer will redirect you to the localhost.

Blocking a website using software

Note: Blocking a site using these steps only blocks the website on one computer. Any other computer, phone, or tablet connected to your computer will be able to access the site you're blocking.
You can also block websites using a software firewall or a filter (such as a parent control Internet filter). Also, most anti-virus software will come with a firewall or have an option to obtain one from them. Filtering software may also be available through the same companies or could be obtained separately. To configure these pieces of software to block websites, you need to follow the instructions provided by the software vendor.

Blocking a website in a browser

Note: Blocking a site in a browser only blocks the site in one browser. Any other browser, computer, phone, or tablet connected to your computer will be able to access the site you're blocking.
Blocking in Firefox
Although not available with the default install of Firefox, there are plenty of add-ons that allow you to block sites in Firefox. Below are the steps on how to install BlockSite, a great add-on to block websites.
  1. Click on the Tools menu and click Add-ons. If you don't see Tools press the Alt key.
  2. In the top-right corner of the Add-ons Manager page, there is a search bar. Perform a search for BlockSite. The first result should be the add-on called BlockSite. Click the Install button to install the add-on.
  3. Restart Firefox to complete the installation.
  4. Click on the Tools menu and click Add-ons. This takes you to the Add-ons Manager page. Click the Extensions tab.
  5. In the listing for BlockSite, click the Options button. The screen below will be shown.
Firefox BlockSite
In the BlockSite Preferences click the Add button. In the window asking for the Web address to block enter the address of the website to block and click the OK button. Click the OK button to exit BlockSite and continue browsing
Blocking in Internet Explorer
Note: If you're running Windows 7 or Windows 8, Windows now handles all the below settings through Family Safety.
  1. Click Tools in the File menu and click Internet Options. If Tools is not visible press the Alt key.
  2. In the Internet Options window click on the Content tab.
  3. Under the Content Advisor heading, click Enable if it has not yet been enabled, or click Settings, enter your supervisor password and click the OK button.
  4. In the Content Advisor window click the Approved Sites tab to show a screen similar to the example below.
Internet Explorer website block
Enter the Web address to block and click the Never button. Click the OK button to exit the Content Advisor window, then click OK again to exit the Internet Options window and continue browsing. Blocking in Google Chrome and other browsers
Blocking a website in Chrome
Chrome does not come included with any type of website blocking tool or feature. However, there are plenty of Chrome Extensions that can be added that allow you to block a website. Visit the Chrome web store and search for "blocksite" to pull up a listing of available extensions that will block websites.

How to Remove or Disable Unwanted Startup Program

You might be suffering slow speed startup of your computer. This slow speed startup is due to unwanted applications entry when computer starts, whether you are using it or not. You can improve computer overall performance or booting time disabling these unwanted programs. You have to remove those unwanted programs to speed up computer startup. Here are some steps posted to remove or disable these unwanted startup applications.

How to Remove Unwanted Startup Program stechnotrick.blogspot.in

 1. Click Start, then Run or press win key+R

2. Type msconfig in popup window and hit Enter
3. You will get System Configuration Utility window, Select Startup tab


Remove unwanted startup program


4. Go through the list appears, disabling the programs you don't need, unticking the box left for them.
5. Restart the computer. The effect would take place after restart your computer.