- •Content
- •Preface
- •Biology as Science and Important Part of Our Life
- •Applying Life Science to Your Life
- •Careers, hobbies and element of personal culture
- •The scientific method
- •1. Basics of organisation of life
- •1.1. Nature and Properties of Life. Cell Theory
- •1.2. Energy and Energy Conversions. Chemistry aspects of life organisation
- •Ionic bonds
- •Ice floats
- •1.3. Life as Phenomenon of Universe
- •Fig. 1.6. Dna structure
- •2. Elements of general biology
- •2.1. Introduction to Cell Biology
- •Internal membranes
- •Pumping Molecules Through Cell Membranes (active transport)
- •Fig. 2.1. Diffusion into and out of cells
- •Fig. 2.2. Active transport of two different ions
- •Autotrophic and Heterotrophic Organisms
- •Stored energy from the sun
- •The role of photosynthetic pigments
- •Identifying Photosynthetic Reactants and Products
- •Respiration in the cells
- •Comparison of photosynthesis and respiration.
- •2.2. Introduction in Genetics
- •Fig. 2.3. Normal human (female) karyotype
- •Fig. 2.4. Dna ladder separates to form two identical dna ladders
- •Mitosis
- •Incomplete Dominance is Neither Dominant nor Recessive
- •X Chromosomes & y Chromosomes
- •Fig. 2.5. Process of meiosis
- •Fig. 2.6. Process of meiosis (continuation)
- •Inheritance of Blood Types
- •Variations and Mutations
- •Initiation of transcription requires a promoter and rna polymerase
- •2.3. The Introduction to Theory of Evolution
- •2.3.3. Classification and Identification
- •The system of Linnaeus
- •The scientific name
- •Bases of Modern Classification
- •Categories of Classification
- •Subdivisions of the Five Kingdoms
- •Identifying Photosynthetic Reactants and Products
- •3. Aspects of biology of viruses, monera, protists, algae, fungi and lichens
- •3.1. Viruses
- •3.1.1. Discovery of viruses. Sizes of viruses
- •Viruses differ greatly in size. They range in length from 0.01 to over 0.3 micrometers; yet over 500 of them can fit on the point of the pin.
- •3.1.2. Characteristics of viruses
- •3.1.3. Kinds of viral infections
- •3.1.4. Defenses against viral infections
- •3.2. Kingdom Monera. Bacteria
- •3.2.1. Bacteria are organisms
- •3.2.2. Main groupes of bacteria Archaebacteria
- •Photosynthetic bacteria
- •Chemosynthetic bacteria
- •Cyanobacteria
- •Some bacteria are helpful
- •Some bacteria are harmful
- •Prevention and control of bacterial disease
- •3.3. Plantlike Protists. Kingdom Protista
- •3.4. Algae
- •Plants that live in water
- •Economic importance of algae
- •3.5. Fungi
- •3.5.1. Terrestrial molds
- •3.5.2. Water molds
- •3.5.3. Slime molds
- •3.5.4. Club fungi
- •3.5.5. Sac fungi
- •3.5.6. Imperfect fungi
- •3.5.7. Fungi and habitats
- •3.5.8. Adaptations to life on land
- •3.5.9. Ecological and economic roles
- •3.6. Lichens
- •3.6.1.Structure
- •3.6.2. Habitats
- •3.6.3. Nutrition
- •3.6.4. Ecological role
- •3.6.5. Reproduction
- •Summary and test questions
- •4. Botany
- •Nonvascular and vascular plants
- •Seed plants
- •4.1. Bryophytes and Mosses
- •4.1.2. Mosses
- •4.2. Ferns
- •4.2.1. Physical structure
- •4.2.2. Life cycle of ferns
- •4.3. Gymnosperms
- •4.3.1. Conifers
- •Importance of conifers
- •4.3.2. Cycads
- •4.3.3. Ginkgoes
- •4.3.4. Gnetales
- •4.4. Angiosperms
- •Kinds of plant tissues
- •Root structure
- •Flowers and sexual reproduction
- •Leaves and water loss
- •Table 4.1 Comparative characteristics of monocots and dicots
- •5.1. Phylum Protozoa
- •5.1.4. Class Sporozoa
- •5.2. Phylum Porifera: Sponges
- •5.3. Phylum Coelenterata
- •5.4. Phylum Plathelminthes. Flatworms
- •5.5. Phylum Nemathelminthes: Roundworms
- •5.6. Phylum Annelids
- •5.7. Phylum Molluska: Mollusks
- •5.8. Phylum Arthropoda
- •Incomplete Metamorphosis
- •5.9. Phylum Chordata
- •Classification and Characteristics of Amphibians
- •The 4,500 species of mammals live throughout the world. Mammals can live in different environments because their flexible body plan has allowed the various species to undergo many special adaptations.
- •5.10. Classification of Kingdom Animalia
- •6. Human Biology
- •Introduction
- •6.1. The skeleton system
- •6.2. The muscular system
- •6.3. The integumentary system
- •6.4. The respiratory system
- •6.5. The excretory system
- •6.6. Nervous control and coordination
- •Introduction
- •6.7. Sense organs
- •Introduction
- •Vision, Hearing, and Balance
- •6.8. Endocrine system
- •Introduction
- •6.9. Circulatory system
- •Introduction
- •Immune Response
- •Immunity
- •6.10. Nutrition and digestion
- •Vitamins
- •Vitamins and Minerals
- •6.11. Reproduction and development
- •Introduction
- •Influence of external environmental factors on human health
- •6.12. World populationand its regulation
- •World population, total quantity and annual increase, 1950–2000 (us Bureau, 2001)
- •7. Biodiversity as phenomenon of life
- •Introduction
- •7.1. Biodiversity and problems of its preservation
- •Biodiversity components and levels (Global, 1995)
- •Quantitative assessment of the species diversity of the planet (Global, 2001)
- •7.2. Biodiversity conservation in Ukraine: conceptual developments and challenges
- •7.3. Protected Areas and Econet of Ukraine as instruments of conservation and innovation
- •7.4. Transboundary protected areas and opportunities for cooperation
- •Carpathians case (successful story)
- •The greening of local environment
- •Conclusion
- •Annex 1. Classification of living organisms
- •Bibliography
- •Additional references
- •Other information resources
- •Terms and definition index
Immune Response
The body also has specific defenses, by which it defends itself against specific pathogens. Body defenders constantly circulate in the bloodstream and tissue fluid, tracking down harmful microorganisms and diseases cells. When they locate their prey, they trigger a precisely targeted attack. These defenders are white blood cells called lymphocytes. The two main types of lymphocytes are B cells and T cells. These are complex white blood cells that stop the progression of diseases and infections.
Every body cell has molecules on its surface that identify it is as “self” – that is, as a part of the body. Foreign substances have surface molecules that tag them as “nonself”. If a surface molecule contacted by a lymphocyte is a “self” marker, nothing happens, and the lymphocyte moves on. If the molecule is a “nonself” marker, however, the body produces an attack on the foreign substance called an immune response. Any molecule that triggers an immune response is an antigen.
When a B cell identifies a “nonself” marker, it carries the pattern for that antigen to a lymph node. The B cell may then become a plasma cell. Plasma cells manufacture proteins that exactly fit the “nonself” surface marker of the antigen. These proteins are antibodies. Each antibody fits – or combats – just one specific antigen. This type of antibody, called a circulating antibody, moves through the body fluids, seeking out the appropriate antigen. When the antigen is located, the antibody hooks on and signals phagocytes to surround and destroy the antigen.
T cells do not produce circulating antibodies. They carry cellular antibodies on their surface. The cellular antibodies latch into an antigen and direct the action of phagocytes. T cells can recognize body cells that have been invaded by cancer and certain viruses. The cancerous cells register as “not quit self,” thus allowing T cells to launch a defense.
Immunity
The body generally requires several days to form antibodies after the first attack by an antigen. Reaction to the first invasion is called the primary immune response. Future responses to the same antigen are rapid because of memory cells. Memory cells are B cells that carry, or “remember”, the antigen pattern.
They produce antibodies immediately if the antigen attacks again. Antibodies produced during such a secondary immune response are stronger and last longer than the original antibodies. Memory cells live for years. New memory cells are produced during each response. As a result, the response is faster and stronger each time. This process of warding off disease through antibodies is immunity. Immunity prevents a person from getting certain diseases, such as measles or chicken-pox, repeatedly.
Problems with the Immune System
Not all "nonself' markers are harmful. Sometimes the body cannot distinguish between harmful and harmless "nonself markers. For example, it may fail to recognize certain pollens as harmless. Reactions called allergies then occur. Although most allergic reactions are not medically serious, some can be life-threatening. One example is the violent immune response some people have to bee venom.
The body occasionally fails to recognize some body cells as "self and attacks them as antigens. Such misdirected attacks occur in autoimmune diseases. Rheumatoid arthritis is an autoimmune disease affecting joint tissue.
The body may also lose its ability to attack invading microorganisms and diseased cells. This condition is called immune deficiency. In its most severe form, immune deficiency is almost always fatal. Its victims suffer from repeated infections and illnesses. Occasionally the deficiency is genetic and is present at birth. More often it develops later in life. AIDS (acquired immune deficiency syndrome) is an example of the latter. AIDS is caused by the human immunodeficiency virus (HIV). The virus kills T lymphocytes, destroying the body's immune system. Rejection of transplanted organs and tissues is also caused by the body's immune system. Transplanted organs are recognized only as "nonself." Previously, drugs were used to suppress a patient's entire defense system to prevent rejection. The patient then became vulnerable to all diseases. Cyclosporine, a recently developed drug, suppresses transplant rejection but does not disrupt other immune functions.