Abiotic and Biotic Factors

Biotic and Abiotic Factors

• Biotic factor: living, or once living, factor in an ecosystem

Biotic and Abiotic Factors

• Abiotic factor: physical, or non living, factor in an ecosystem– Abiotic factors were

NEVER living

Characteristics of Living Things

• Universal genetic code (DNA)

• Made up of cells

How do we know something is alive?

• Reproduction

• Growth and development

How do we know something is alive?

• Response to environment

• Energy

How do we know something is alive?

• Maintain stable internal environment (homeostasis)

• Adaptation and Evolution

How do we know something is alive?

Is it ALIVE?!• Chalk• Fire• Earthworm• Apple seed• Pine tree• Mildew• Sand• Potato• Rose bush• Ocean

• Corn• Mouse• Dirt• Virus• Mushroom• Frog• Snake• Milk• Blood• Chair

As a pair, tell me whether each object above is alive or not alive. Explain your reasoning for each using what you just learned about living vs. non-living things.

Organisms in their Environment

• Individual• Species • Population• Community• Ecosystem• Biome• Biosphere

Classification of Living Things

Classification

• Grouping organisms based on external characteristics can cause problems

• Phylogeny: evolutionary relationships– Scientists now group based on evolutionary

descent, not just physical characteristics– This is called evolutionary classification

Cladograms

• Shows evolutionary relationships among groups of organisms

• Derived characters: characteristics that appear in recent parts of a lineage but not in older members

How are organisms classified?

• Similarities in:– Habitat– Adaptations– DNA sequences and number of genes– Evolutionary relationships

• Homologous structures• Similarities in embryology

Hierarchy of Classification

KingdomPhylum

ClassOrderFamilyGenus Species

Kingdoms

Five Kingdoms• Monera• Protista• Fungi• Plantae• Animalia

Six Kingdoms• Eubacteria• Archaebacteria• Protista• Fungi• Plantae• Animalia

Animals

• Multicellular• Heterotrophic• No cell walls

Animal Phyla• Porifera• Cnidaria• Ctenophora • Platyhelminthes• Annelids (Annelida)• Nematoda• Echinoderm

(Echinodermata)• Arthropods (arthropoda)• Mollusks (molussca)• Chordates (chordata)

Characteristics of Vertebrates• Bilateral symmetry • Two pairs of appendages• Outer covering of protective skin• Well-developed body cavity (coelom) completely lined with epithelium

(cellular tissue), that may be divided into 2 to 4 compartments. • Internal skeleton of cartilage and bone• Brain enclosed by skull • Well-developed sense organs (eyes, ears, nostrils) located on the head

(cephalization)• Respiratory system: gills or lungs • Closed circulatory system with ventral heart and median dorsal artery. • Genital and excretory systems closely related, utilizing common ducts and

pathways• Digestive tracts with two major digestive glands (liver and pancreas)

Types of Vertebrates

• Myxini - hagfishes • Cephalaspidomorpha - lampreys• Chondrichthyes - cartilagenous fishes • Osteichthyes - bony fishes • Amphibia - frogs, toads, salamanders• Reptilia - turtles, snakes, lizards• Aves - birds • Mammalia - mammals