Animal Behavior and Energy Conservation

Metabolism and Survival

• Key Area 4 focuses on metabolism in conformers and regulators.
• Subsection (a) details abiotic factors.
• Key abiotic factors influencing metabolic rate include pH, temperature, salinity, and moisture.
• Abiotic factors such as temperature, pH, and salinity affect an organism's metabolic rate.

Conformers

• Conformers' internal environments mirror their external environments.

• Snakes, lizards, and frogs are examples of conformers.

• Their internal environment is dependent on abiotic factors affecting the external environment.

• Advantage: Low metabolic costs as they don't regulate internal environment.

• Disadvantage: Restricted to a narrow ecological niche, intolerant of low temperatures.

• Behavioral strategies: Bask in sunlight to raise body temperature.

Regulators

• Regulators use their metabolism to maintain a constant internal environment, regardless of external conditions.
• Dogs and humans are examples of regulators.
• Advantage: Occupy a larger range of ecological niches.
• Disadvantage: Higher metabolic costs needed for homeostasis.

Negative Feedback Control

• Homeostasis is maintained through negative feedback.
• This process maintains stable internal conditions (e.g., temperature) despite external changes.
• Regulators need energy for homeostasis to maintain internal conditions.

Thermoregulation

• Thermoregulation is an example of negative feedback.
• It's the process by which mammals maintain a constant body temperature of 37°C.
• Hypothalamus is the body's temperature monitoring center.

Correction of Overheating

• Vasodilation of blood vessels increases blood flow to the skin, increasing heat loss via radiation.
• Increased sweating uses body heat to evaporate water, cooling the skin.
• Decreased metabolic rate reduces heat production.

Correction of Overcooling

• Vasoconstriction of blood vessels reduces blood flow to the skin, reducing heat loss via radiation.
• Contraction of hair erector muscles traps a layer of insulating air.
• Shivering produces heat through muscle contractions.
• Increased metabolic rate increases heat production.

The Skin

• Vasodilation: Blood vessels dilate, increasing heat loss through radiation.
• Vasoconstriction: Blood vessels constrict, conserving heat.

The Hypothalamus

• The hypothalamus acts as the body's temperature control center.
• It receives information about body temperature from receptors and sends signals to effectors for corrective responses.

Why is Maintaining 37°C Important?

• Optimal enzyme activity and high diffusion rates are maintained for efficient metabolism.

Conformers Vs Regulators

• Conformers: Body temperature changes with the environment.
• Regulators: Maintain constant body temperature regardless of environmental changes.

Surviving Adverse Conditions

• Adaptations for surviving adverse conditions involve dormancy (e.g., hibernation, aestivation, daily torpor).
• These involve reduced metabolic rate, heart rate, breathing rate, and body temperature to conserve energy.
• Some animals migrate to better environments to avoid adverse conditions.

Predictive Dormancy

• Trees shed leaves in autumn in response to decreasing day length and lower temperatures.
• It's a preparatory measure for winter conditions.

Consequential Dormancy

• Animals like frogs become dormant when hot and dry conditions arise.

Hibernation

• A form of dormancy mammals use during winter to survive low temperatures.
• Reduced metabolic rate, lower body temperature, slower heart and breathing rates are adaptations.

Aestivation

• A type of dormancy for surviving high temperatures and drought.
• Animal metabolic rate decreases to withstand harsh conditions.

Daily Torpor

• A daily period of reduced metabolic activity found in some mammals (e.g., humans, bats).
• It's a strategy to conserve energy.

Migration

• A strategy for avoiding adverse metabolic conditions.
• Migratory animals move to more favorable environments.

Studying Migratory Animals

• Methods include leg-ringing, satellite tracking for collecting data on migration patterns.

Migratory Behaviour

• Innate behavior is inherited and inflexible.
• Learned behavior is influenced by experience, adjusting to different environments.

Experiments on Migration - Displacements, Tendencies, Cross-fostering

• Researchers use these experiments to determine what aspects of migration are innate, and which are learned.

Microorganisms

• Microorganisms are used in various industrial processes and research due to their adaptability, quick growth rate, and ability to produce diverse metabolic products.
• Growth factors influence microbial growth. The ingredients in the growth medium affect their growth rate.

Fermenters

• Closed systems are used for microorganisms to grow optimally.
• Factors including temperature, oxygen levels, and pH are carefully controlled using external systems.

Microbial Growth Phases

• Lag phase: Induced enzyme production to use new substrates for growth.
• Log/exponential phase: Rapid increase in cell number.
• Stationary phase: Nutrients deplete, accumulation of waste/toxic metabolites .
• Death phase: Cell number decreases due to lack of nutrients or buildup of toxic substances.

Cell Counts

• Viable counts only count living cells.
• Total counts include both living and dead cells.

Domains of Life

• Microorganisms come from three domains: Bacteria, Archaea, and Eukaryotes.

Importance of Controlling pH

• Buffers are added to maintain the pH of growth media to ensure optimal growth of microorganisms.

Genetic Control of Metabolism: Improving Wild Strains

• Mutagenesis is the creation of mutations to increase the frequency of desirable traits in microorganisms.
• Recombinant DNA technology involves transferring genes to produce desired products.

Plasmids as Vectors

• Plasmids are used to carry genes for industrial production purposes.
• Plasmids have a restriction site, selectable markers, and an origin of replication to be good vectors.

Vectors: Restriction Sites, Selectable Markers, and Origin of Replication

• Restriction endonucleases cut DNA at specific sites for transferring genes.
• Selectable markers allow researchers to identify cells carrying the desired gene.
• Origin of Replication allows for the multiplication of the required gene.

Vectors: Regulatory Sequences

• Regulatory sequences control gene expression, impacting the production rate of desired products within microorganisms.

Ligase

• Ligase is an enzyme used to seal the desired gene fragment into the plasmid.