Chapter 1: Biology and You Holt

Section 1: Themes of biology Characteristics of Living organisms Unifying Themes of Biology

Characteristics of living organisms Organisms- living things, such as people, plants, and animals Biology- study of life Every living organism: composed of one or more cells Able to reproduce Obtains and uses energy to run the processes of life

Properties of life Cellular organization Reproduction Metabolism Homeostasis Heredity Responsiveness Growth and development

Unifying Themes of Biology Cellular structure and function Reproduction Metabolism Homeostasis Heredity Evolution Interdependence

Theme 1: Cellular Structure and function All living things are made of one or more cells Cells are highly organized, tiny structures with thin coverings called membranes The smallest unit capable of all life functions Single celled/ multicellular

Theme 2: Reproduction Reproduction- the process by which organisms make more of their own kind from one generation to the next An essential part of living

Theme 3: Metabolism Metabolism- the sum of all of the chemical reactions carried out in an organism Almost all the energy used by living organisms is originally captured from sunlight Plants, Algae, Bacteria- Photosynthesis

Theme 4: Homeostasis All living organisms must maintain a stable internal environment in order to function properly. Homeostasis- the maintenance of stable internal conditions in spite of changes in the external environment

Theme 5: Heredity Passing of traits to offspring from the parent Gene- the basic unit of heredity (DNA) Heredity- the passing of traits from parent to offspring Mutation- a change in the DNA of a gene Can cause cancer

Theme 6: Evolution Evolution- Change in the inherited characteristics of species over generation Species- a group of genetically similar organisms that can produce fertile offspring Natural selection- survival of the fittest Charles Darwin

Theme 7: Interdependence A biological community is a group of interacting organisms Ecology- branch of biology that studies the interactions of organisms with one another and with nonliving parts of their environment Food webs

Section 1 Review Identify the seven properties that all living organisms share. Relate three of the seven major themes of biology to the life of a harp seal. Name the very small, organized structure that is bound by membrane and that is the basic unit of structure and function in all organisms.

Section 1 Review (cont) Define homeostasis and metabolism, and describe their differences. If you find an object that looks like an organism, how might you determine if your discovery is alive? The mutation that results in sickle cell anemia produces effects that are A. Only harmful b. Only positive C. Both harmful and positive D. unimportant

Section 2: Biology in your World Solving real world problems Fighting diseases

Solving Real World Problems Preserving the environment Improving the food supply Understanding the Human genome

Preserving Our Environment More the 6 billion people live on Earth How can this be a problem?

Improving food supply Genetically engineered crops

Understanding the Human Genome Hunam genome project Genome- the complete genetic material contained in a individual Contains 3 billion individual units

Aids Cancer Emerging diseases Gene Therapy Fighting Disease Aids Cancer Emerging diseases Gene Therapy

AIDS A fatal disease caused by HIV HIV- a virus that attacks and destroys that human immune system Transmitted by contact with body fluids from an infected person No vaccine presently

Cancer A growth defect in cells A breakdown of the mechanism that controls cell division Prevention methods: don’t smoke..Lung cancer

Emerging Diseases West Nile Virus Transmitted by misquitoes Infects humans, birds, horses, and possibly other animals Mad cow disease Infected by eating meat of infected cattle

Gene Therapy Cystic fibrosis- a fatal disorder in which a thick, sticky mucus clogs passages in many of the body organs Gene therapy- the replacement of a defective gene with a normal version Muscular dystrophy, hemophilia

Section 2 Review Describe the relationship between scientific research and the use of the environmental resources Explain how genetic engineering can improve food supplies. Describe one problem that scientists must overcome to develop a vaccine for HIV.

Section review (cont) Explain how gene therapy might be used to treat cystic fibrosis. Do you agree or disagree that a knowledge of biology is essential in the battle against diseases? Explain your answer. One goal of researchers who transpalnt beneficial plant genes into other plants is to: A. Accelerate extinction B. Cure cancer C. Halt the spread of AIDS D. Reduce pesticides use

Section 3: Scientific Processes Observation: the basis of scientific research Stages of Scientific Investigation Scientific explanations

Observation: The basis of Scientific Research Solving scientific puzzles

Solving scientific puzzles Observation- the act of noting or perceiving objects or events using senses Look at your book: How does it feel? What does it look like?