Presentation on theme: " All living things are made up of one (unicellular) or more cells (multicellular). › Cell - smallest unit capable of performing all life’s processes."— Presentation transcript:
All living things are made up of one (unicellular) or more cells (multicellular). › Cell - smallest unit capable of performing all life’s processes.
Living organisms have organization. › Organization - high degree of order within an organism’s internal and external parts and its interaction with the living world. Highest level of organization- organism is made up of organ systems that carry out specific functions within the organism (Ex: digestive system).
Living things respond to a stimulus. › Stimulus - physical or chemical changes in an organism’s internal or external environment. › This is essential to survival.
Homeostasis - maintenance of a stable internal environment despite the constant changing of an organisms external environment. Organisms have built in system that maintains stable internal conditions, such as: › Temperature › Water content › Nutrient uptake by cell
Energy is required to power ALL life’s processes, such as › Growth and development › Movement › Repair Metabolism - sum of all the chemical reactions that take in and transform energy and materials from the environment.
Photosynthesis › Plants, algae, phytoplankton, and some bacteria capture and use the sun’s energy to make sugar molecules. Organisms that cannot make their own food must get their food from other organisms.
Nonliving things (Ex: icicles) grow by accumulating more of the same material (Ex: ice) of which they are made. LIVING things grow through division and enlargement of cells. › Living multicellular organisms mature through cell division, cell enlargement, and development.
Development - process by which organisms become more adult. › Involves: cell division, cell differentiation, or specialization. › Your body contains trillions of specialized cells (Ex: nerve cells, blood cells, skin cells..), all of which originated from a single cell, the fertilized egg.
Reproduction - Organisms produce more organisms like themselves. › NOT needed for individual’s survival. However, reproduction is ESSENTIAL to survival of a species. Hereditary information is passed from parent to offspring through DNA. Short segments of DNA make up individual genes.
Two major types of reproduction: › Sexual reproduction- hereditary information recombines from TWO organisms. Offspring are similar but not identical to either parent. Ex: Frogs › Asexual reproduction- herditary information comes from a single parent organism. Offspring are identical to parent. Ex: bacteria
The basic GENETIC characteristics of an individual organism do not change over their lifetime. Populations of organisms DO change through time, or evolve. › This is critical to survival in a changing world. › Explains the diversity of life-forms we see on Earth today.
Living things come in many varieties (huge diversity ).
Although diverse, living things are characterized by unity, or things they have in common. › Genetic code- rules governing how cells use hereditary information. › Organelles that carry out life’s functions.
“Tree of Life”- a model of the relationships by ancestry among organisms. › Living things share certain genes, yet no two types of organisms share all the same genes. › Three main lineages, called domains. Organisms found on closer branches (lineages) have more similar sets of genes. 1.Bacteria 2.Archaea 3.Eukarya - complex cells containing a nucleus. Less complex cells
Another system of grouping organisms divides life into six categories called kingdoms. › 4 kingdoms within domain Eukarya Kingdoms Animalia, plantae, fungi, protista › 1 kingdom within domain Archaea Kingdom Archaea › 1 kindom within domain Bacteria Kingdom Bacteria
Ecology - study of how organisms interact with each other and the environment. › Study single species as well as ecosystems. Ecosystems - communities of species and their physical environment. Studies have shown that species depend on each other and their physical environment for survival.
Evolution - (decent with modification) process in which inherited characteristics within POPULATIONS change over generations. › Can lead to genetically distinct populations and development of new species.
Theory of Evolution by Natural Selection › Natural Selection - organisms with certain favorable traits survive and reproduce more than those without them. Those traits that increase an organism’s ability to survive and reproduce are called adaptations.