module 4-biomes & plant structure🌳

What is ecology?

Study of living organisms and their interactions with the environment.

What are the 4 levels of ecology?

Ecosystem, community, population, organism.

What is an ecosystem?

Living organisms interacting with each other and their environment.

What is a community?

All populations of different species living in an area.

What is a population?

Members of the same species living in an area.

What is an organism?

One individual living thing.

What are 4 abiotic environmental factors?

Sun/energy, soil/nutrients, rainfall, temperature.

What does sun/energy provide for organisms?

Energy for photosynthesis.

What can soil/nutrients affect?

Abundance of organisms.

What can rainfall affect?

Cellular processes.

What factors classify biomes?

Climate, soil, precipitation, and vegetation.

What factors classify land cover?

Human activity, concrete, buildings, and suburban areas.

What does NEON stand for?

National Ecological Observatory Network.

What is the purpose of NEON?

Observe differences and make connections across the U.S.

Tropical Rainforest

Equatorial areas; 68–93°F; 125–600 cm rain; broad leaves; no seasonal leaf loss.

Savanna

Africa, South America, northern Australia; 75–84°F; 10–40 cm rain; grasses, forbs, scattered trees.

Subtropical Desert

15–30° N/S; 104°F days; −22–32°F nights; fewer than 30 cm rain; little vegetation; low diversity.

Chaparral (Shrubs)

Southern California, Mediterranean coasts, Australia; 65–75 cm rain, mostly winter; shrubs, short dense canopy.

Temperate Grasslands (Prairies)

North America, Eurasia; hot summers, cold winters; 25–75 cm rain; mostly grasses, few trees.

Temperate Forests

Mid-latitudes; −22–86°F depending on season; 75–150 cm rain; deciduous trees; seasonal leaf loss.

Boreal Forests

South of Arctic Circle: Canada, Alaska, Russia; cold dry winters; short cool wet summers; 40–100 cm; evergreen trees.

Arctic Tundra

Arctic regions; −29°F winter to 37–52°F summer; very little rain; short growing season; low species diversity.

Positive Feedback

A process that amplifies or increases the original change.

Acclimation

An individual adjusts to environmental changes during its lifetime.

Selection Pressure

An environmental factor that affects survival and reproduction.

Photosynthesis

Process plants use to convert light energy into chemical energy.

Respiration

Process cells use to break down molecules and release usable energy.

Terrestrial Biosphere

All land-based ecosystems and living organisms on Earth.

Woody Trees (Deciduous)

Medium surface area; high height.

Woody Trees (Conifers)

Medium surface area; high height.

Woody Shrubs

Medium surface area; low height.

Broadleaf Forbs

High surface area; low height.

Ferns

High surface area; low height.

Mosses

High surface area; low height.

Graminoids/Grasses

high surface area; low height; more drought tolerant than trees.

Shoot System

Vegetative, non-reproductive parts above ground, including leaves and stems; reproductive parts include flowers and fruits.

Root System

Absorbs water and minerals, anchors the plant, and supports the plant.

Meristematic Tissue

Can differentiate; immature cells used when needed for growth.

Apical Meristem

Increases height; found at the tips of shoots and roots.

Lateral Meristem

Increases the girth/width of the plant.

Intercalary Meristem

Found in monocots; allows leaf elongation and growth, especially in grasses.

Permanent Tissue

No longer divides; cells are specialized for specific functions.

Dermal Tissue

Covers and protects the plant; acts like the plant's skin.

Vascular Tissue

Transports water, minerals, and sugars throughout the plant.

Ground Tissue

Performs photosynthesis, provides support, and stores water and sugars.

Parts of a Leaf

Lamina, petiole, stipules, midrib, and margin.

Lamina

Broad, flat part of the leaf.

Petiole

Stalk attaching the leaf to the stem.

Stipules

Structures at the base of the petiole.

Midrib

Prominent central vein of the leaf.

Margin

Edge of the leaf.

Epidermis

Outermost layer of the leaf; upper epidermis provides protection and lower epidermis contains stomata.

Cuticle

Waxy outer layer that helps prevent water loss.

Mesophyll

Internal leaf tissue containing palisade and spongy mesophyll.

Palisade Mesophyll

Tightly packed cells; major site of photosynthesis.

Spongy Mesophyll

Loosely packed cells with spaces that allow gas exchange.

Water Potential

Water moves from high water potential to low water potential.

Transpiration

Loss of water through evaporation; creates negative pressure that pulls water up the plant.

Stomata

Small openings in leaves that regulate gas exchange and water loss.

Stomata at Night

Stomata close at night to reduce water loss.

Cohesion

Attraction between water molecules that helps keep water together in the xylem.

Adhesion

Attraction between water and xylem walls that helps keep water in the xylem.

Cavitation

Formation of gas bubbles in the water column that can break the continuous flow of water.

Water Movement in Plants

Water moves upward through the xylem because transpiration creates negative pressure; cohesion and adhesion help maintain the water column.

Plant Tissue Organization

From outside to inside: dermal tissue, ground tissue, then vascular tissue.