Studying LifeSection 1.3

Characteristics of Living Things• Biology- Study of life

• No single characteristic can describe a living thing.

• Some nonliving things share traits with living things.

Characteristics of Living Things (cont.)

• Basic units, which are known as cells.

• Based on a universal genetic code.

• Obtain and use materials for energy, to grow and develop, reproduce.

Characteristics of Living Things (cont.)

• Respond to their environment (stimuli)

• Maintain a stable internal environment (homeostasis)

• “Change” over time.

Cells• Cells are the basic units

of life.

• Although they are small, they are highly complex and organized.

• They can grow, respond to their surroundings, and reproduce.

Universal Genetic Code

• The complex information found in organisms that allow them to live, grow, and reproduce is written in a molecule called DNA.

• Every organism on Earth is identical to another through life’s genetic code.

Living Things Grow and Develop

• An organism follows a pattern of growth and development, based on its genetic code.

• As cells divide, they differentiate. They will look different and begin to perform different functions in the organism.

Living Things ReproduceAsexual Reproduction• Process of reproduction involving

a single parent that results in offspring that are genetically identical to the parent.

Sexual Reproduction• Type of reproduction in which

cells from two parents unite to form the first cell of a new organism

Maintaining a Stable Internal Environment

• Organisms have to keep their internal environment relatively stable in order to survive. This is known as homeostasis.

Living Things Get and Use Material and Energy

• Every organism has to take in materials and energy to grow, develop, and reproduce.

• Chemical reaction that a living thing builds up or breaks down those materials are called metabolism.

Living Things Evolve

• Organisms as a group evolve over time.

• There is a common origin for all organisms…more than 3.5 billion years ago!

Big Ideas in Biology• Biology revolves around interlocking big ideas:

– Cellular Basis of Life– Information and Heredity– Matter and Energy– Growth, Development, and Reproduction– Homeostasis– Evolution– Structure and Function– Unity and Diversity of Life– Interdependence in Nature– Science as a Way of Knowing

Fields of Biology• Biology includes many overlapping fields that use different

tools to study life from the level of molecules to the entire planet.

Fields of Biology (cont.)• Some examples are: Anatomy Ecology Genetics Marine Biology

Nutrition Zoology Paleontology