Chapter 1: The Nature of Life

What Does it Mean to be “ALIVE?” Organism: A living thing that can carry out the basic life functions. There are six basic kingdoms of life on the planet: 1. Archaebacteria (Prokaryotic) 2. Eubacteria (Prokaryotic) 3. Plantae (Eukaryotic) 4. Animalia (Eukaryotic) 5. Fungi (Eukaryotic) 6. Protists (Eukarytic)

Prokaryotic Verses Eukaryotic Smaller and more simple No membrane bound organelles No nucleus Example: Any bacteria Eukaryotic: Larger and more complex Membrane bound organeles True Nucleus Example: anything except bacteria

Kingdom of Life?

Kingdom of Life?

Kingdom of Life?

Kingdom of Life?

Kingdom of life?

Characteristics of an organism (characteristics of life) 1. Must be organized and contain many complex substances (organic) Organisms are composed of the following: carbohydrates, proteins, lipids, Nucleic Acids,

Characteristics of life…. Must be made of cells. Either Prokaryotic (both types of bacteria) or Eukaryotic (plants, animals, fungi, protists)

Characteristics of life….. Requires usable Energy in the form of ATP ATP is Produced through the process of cellular respiration

Characteristics of life…. Must have a definite form and a limited size

Characteristics of life…. Limited life span

Characteristics of life…. Must Grow In single celled organisms, growth occurs through the cell increasing in size. In multicellular organisms, growth occurs through cell division and the cells increasing in size.

Characteristics of life…. Respond to its environment The factors that cause a response are called stimuli

Characteristics of life…. Able to Reproduce Either Asexually (single celled organisms) or sexually (most multicellular organisms)

Characteristic of life… Change over time as a species… Evolution

Life characteristics Continued: Non living things may have some but will not have all! Examples: Car, fire, ect….

Homeostasis… The process of maintaining a stable internal environment both within the cellular level and within the organism itself. All organisms must maintain some kind of stable internal environment in order to function. Maintaining homeostasis is a vital to an organisms survival. If homeostasis is not maintained, the organism will die.

Maintaining homeostasis in Humans Cooling down: Sweat- cools the body through evaporation cooling. Heating up: shivering- as body moves, heat energy is produced. Blood sugar: Glucagon raises blood sugar, Insulin lowers blood sugar. Blood pressure: arteries constrict to raise blood pressure and relax to lower it.

What Life Processes are we going to discuss? (come up with Acronym) Nutrition (Way of obtaining energy) Transport system within the organism. Respiration to make ATP Synthesis (creation of materials) Excretion (getting rid of waste) Regulation (Homeostasis) Reproduction (creation of new organisms) Metabolism (perform chemical reactions) Growth

Nutrition Definition: taking materials from an external environment and converting into forms that can be used. Nutrients: Substances an organism needs for growth, energy, repair, and maintenance

Basic Types of Nutrition Autotroph: makes own nutrients from simple substances in its environment Phototroph: uses energy from light to create nutrients Chemotroph: Uses Chemicals to create nutrients Heterotroph: relies on other organisms for nutrients

Nutrition Continued Ingestion: Taking in food items from the environment Digestion: The act of breaking down of nutrients into simple forms that the organism can use.

More Life Processes Transport system: Process by which substances are moved around the body and enter and leave the Cells Xylem + Phloem, Circulatory system Respiration: Releasing the chemical energy stored in nutrients 1. Aerobic Respiration: uses oxygen, Produces CO2 and H2O 2. Anarobic Respiration: Does not require oxygen Creates either lactic acid or alcohol

Life Processes Synthesis: Combing simple substances chemically to make new more complex substances Assimilation: Incorporation of material into an organism’s body Excretion: removal of waste from an organisms body Regulation: activities that help maintain homeostasis

Life processes Reproduction: Process by which organisms make new organisms of the same species Asexual : Single individual produces an identical individual Sexual: Two parents contribute genetic material and offspring is non- identical

Almost done Life processes… Metabolism: All The chemical reactions within cells that either break substances down or build them up. Growth: increase in size Single celled (unicellular): Cell increases in size Many celled ( multicellular): Cells increase in size and increase in number. Cellular specialization: cells have certain functions

Bioethics - The study of controversial ethics related to biology Examples: clone, life support, animal testing, Genetic modification