What Does It Mean to Be Alive Characteristics

What Does It Mean to Be Alive? Characteristics of life

LIFE!!! All living organisms share some basic properties Characteristics of Life Video

Made Up of Cells Cell ◦ Smallest unit (part) of an organism that is considered alive ◦ Unicellular vs Multicellular Unicellular – Bacteria and Protists Multicellular – Cells have specialized functions within the organism

Reproduce Reproduction ◦ Process of producing new organisms of the same type ◦ Necessary for the survival of the species ◦ Asexual vs. Sexual Asexual - A single parent organism reproducing by itself Sexual - Two different parent organisms (male and female) contribute to produce a new organism (offspring)

Based on a Universal Genetic Code All organisms shared the same basic genetic code, but every organism has a different arrangement of the genetic code Genes carry hereditary information ◦ Genes are composed of DNA is a type of BIOMOLECULE Nucleic Acid DNA (Polymer) Nucleotides (Monomer) DNA is passed to our offspring

Grow and Develop Growth ◦ Physical change in size, over a period of time Development ◦ Change in the physical form or physiological make-up of an organism Physiology ◦ Study of functions in living systems. How your body works.

Obtain and Use Energy Living organisms need energy to grow, develop, repair damage, and reproduce Metabolism ◦ The sum of all chemical reactions in an organism Breaking down big molecules into smaller molecules +building up big molecules = Metabolism

Respond to Their Environment Organisms are sensitive and react to immediate changes or needs (stimulus) ◦ Stimulus: Something that causes a physiological response Examples of Stimuli (plural for stimulus) • • • Light Temperature Sound Gravity • Heat • Water • Pressure

Maintain Homeostasis (Internal Balance) ◦ External conditions may change dramatically, but all organism must keep internal conditions relatively steady What are some examples of stable conditions in our body that are necessary for life? Body temperature Blood volume p. H balance Water balance

Adapt to Their Environment Through Evolution Over multiple generations, organisms must change when adapting to their environment Evolution ◦ Change in characteristics of populations/species over time resulting from mutations and natural selection Natural Selection ◦ Gradual natural process by which biological traits become more or less common in a population through reproduction and environment Adaptation ◦ A process that enables organisms to become better suited to their environment