Natural Selection Best adapted survives and reproduces!

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Natural Selection

Best adapted survives and reproduces!

English Peppered MothExample

Before industrial revolution After industrial revolution

English Peppered Moth Example

Galapagos Ground FinchStudy by Rosemary and Peter Grant

In dry years average beak depth increases-birds with large bills survive better-more large seeds available

In wet years average beak depth decreases-birds with small bills survive better-more small seeds available

Antibiotic Resistance

• Antibiotic resistance happens fast!• Antibiotics: chemicals that destroy

microorganisms like bacteria• Genetic variation = bacteria are not all the same• Selective pressure for resistance = bacteria that

are resistant survive and their offspring survive• Resistance comes from: 1. inappropriate use

2. patients who do not take whole prescription• Antibiotic use in livestock: 1. used in healthy

animals 2. causes resistant bacteria

Antibiotic resistant gene

Bacteria with antibiotic resistant gene survive

AND REPRODUCE THE NEXT GENERATION!!

Properties of Water: Cohesion and Adhesion

Cohesion: holds water together within a vesselAdhesion: water sticks to vessel wall resisting gravity

High Surface Tension

Properties of water:(Due to hydrogen bonding)

• Cohesion/Adhesion

• High surface tension

• High specific heat

• High heat of vaporization

• Lower density as a solid than a liquid

• Good solvent

Solute + Solvent = Solution

Acids, Bases and Buffers

Acid: high H+

Base: low H+

pH: measure of H+

Acid Rain:Destroys Lakes

Buildings and Statues

Ocean Acidification

• Overproduction of carbon dioxide through fossil fuel combustion

• Oceans absorb carbon dioxide

• Ocean acidification: CO2 dissolves in seawater and reacts with water to form carbonic acid (lowers ocean pH)

• Less carbonate for reef calcification

CO2 dissolved in ocean reacts with water to form carbonic acid

Carbonic acid dissociates into bicarbonate and hydrogen ions

Hydrogen ions form more bicarbonate with carbonate ions making them unavailable for calcification by marine animals such as coral

Coral reefs increase biodiversity,protect shorelines, feeding ground for fish species (fisheries), tourism

Succulent = stores water

Connection between photosynthesis andcellular respiration

Strategies for Body Temperature

• Endotherm: most body heat obtained internally (from metabolism)

• Endotherms tend to be homeotherms (maintain a constant body temperature)

• Ectotherms: most body heat obtained externally (from environment)

• Ectotherms tend to be poikilotherms (allow body temperature to fluctuate with environmental temperature)

Modes of Heat Loss and Gain

Radiation: heat loss or gain by a difference in body temperature and the environmentConduction: heat loss or gain by direct contact with an objectConvection: heat loss or gain by wind or water currentsEvaporation: heat loss only, cooling mechanism

Body Temp = Heat Produced + Heat Gained – Heat Lost

(By Metabolism) (From Environment) (To Environment)

Osmoregulation: salt and water balance

What does osmoregulation for us?

Special adaptations: Kangaroo rats

Excretion of nitrogenous wastes

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