Animal & Plant Physiology: Course Intro

Introductory Biology III: Animal & Plant Physiology

• Physiology studies normal function in living systems.
• Pathophysiology studies disordered physiological processes linked to disease.
• The course format will include lectures and labs.
• Canvas will be used for assignments, readings, and updates.
• Student Led Inquiry (SLI) group presentations are part of the course.
• All groups are required to meet prior to their presentation.
• Regular Canvas checks are necessary.
• Lab handouts are provided weekly.
• Labs are required, and cannot be made up without prior arrangement.

Strategies for Success

• Attending class is important.
• Active participation is encouraged.
• Assigned readings are the student's responsibility.
• "Hands-on" lab experience is important.
• Collaboration with classmates is beneficial.
• Seek help when needed, and clarify confusion early.
• Reflect on your own learning style to optimize studying.
• Engage with the classroom learning community.

Course Components

• Peer Facilitators will assist with:
  • Breakout sessions.
  • Student success
  • Discussion Boards.
  • Peer contact.
  • Collaborative activities.
• Class Panopto recordings posted on Canvas
• Prompts assigned in Canvas

Overall Course Goals

• Exploring the relationship between structure (anatomy) and function (physiology) at all levels of organization.
• Understanding "Homeostasis" which is the maintenance of a constant internal environment. -Recognizing of optimal physiological function in supporting “health”.
• Recognize the role of pathophysiological dysfunction in “disease, in both animals and plants.

Animal Form and Function

• Today's class goals include exploring the relationship between structure and function at different levels and examining body size's impact on physiology, as well as surface area to volume considerations.
• A goal also includes developing an understanding of "Homeostasis," focusing on thermoregulation.

Structure and Function

• Anatomy is the study of an organism's physical structure.
• Physiology is the study of how physical structures function in an organism.
• There is a significant amount of diversity in anatomical and physiological traits across animals.

Adaptation and Acclimatization

• Adaptations are genetic changes over long periods that allow populations to survive and reproduce in specific environments.
• Adaptations are heritable traits increasing the fitness of a population.
• Adaptations depend on the alleles present in a population and involve "trade-offs" where traits cannot be simultaneously optimized.
• Acclimatization involves phenotypic changes in an individual in response to short-term environmental changes.
• Llamas living at high altitudes have special hemoglobin to efficiently bind oxygen.

Structure and Function Relationships

• Correlations between structure and function exist at the molecular, cellular, tissue, organ, organ system, and organism levels.
• Tissues are groups of cells performing a unit function with specialized cell types.

Tissue Types

• There are four adult tissue types with correlated structure-function relationships: connective, nervous, muscle, and epithelial.
• Lab sessions will include histological examinations of different tissue types.
• Connective tissue includes loose, dense, fluid, and supportive types embedded in matrices.
• Connective tissue functions include energy storage, organ protection, a structural framework, body tissue connection/compartmentalization, hormone supply, nutritional support, and defense reactions.
• Nervous tissue is composed of neurons and supporting glial cells.
• Neurons are “conducting” cells, while neuroglial cells provide support.
• Muscle tissue types include skeletal, smooth, and cardiac, differing in voluntary control, cell structure, and striation.
• Epithelial tissue forms interfaces, provides protection, and regulates transfer.
• Epithelial tissue is made of tightly packed cells

Surface Area and Volume

• The rate of oxygen and nutrient diffusion into cells and waste diffusion out depends on available surface area.
• Nutrient use and waste production depend on cell volume.
• As cube side length increases, surface area and volume increase exponentially, whereas the SVR ratio decreases exponentially.
• High body temperature can be caused by infections, medication overdose, or overactive thyroid.
• Low body temperature can be caused by alcohol abuse, anesthesia or low iodine levels.

Metabolic Rate

• Metabolic rate is an individual's overall energy consumption rate.
• Basal Metabolic Rate (BMR) is the rate of oxygen consumption at rest under specific conditions.
• Smaller animals have higher BMRs per gram than larger animals.
• Mass-specific metabolic rate must decrease as organism size increases to maintain the material exchange.

Homeostasis

• Homeostasis is stability in the chemical and physical conditions within an animal’s cells, tissues, and organs; surrounding environmental conditions may change, internal and physical states are kept within a tolerable range.
• Conformational homeostasis involves passively matching the body's internal conditions.
• Regulatory homeostasis involves actively adjusting internal conditions.

Role of Regulation and Feedback

• Many animals have regulatory systems to monitor internal conditions like temperature, blood pressure, pH, and glucose.
• Each variable has a set point and if a change occurs, the homeostatic system acts to restore balance.
• A homeostatic system has three components: sensor, integrator, and effector.

Regulation and Feedback in Homeostasis

• The stimulus is a change in a variable which is detected by a receptor (sensor).
• Integrator evaluates incoming sensory information
• Effector responds to restore the desired internal condition/original range.
• Thermoregulation is critical in animal physiology for the survival of individuals by maintaining stable body temperature.
• Animals exchange heat with their environment via radiation, evaporation, convection, and conduction.

Temperature Regulation in Mammals

• Mammals regulate temperature through behavioral and physiological responses that move body temperature back toward setpoint.
• Feedback systems involve "antagonistic pairs," where one set of responses increases a parameter while another set decreases it.
• Arteriole dilation releases heat, while arteriole constriction conserves heat.
• Countercurrent heat exchangers conserve heat by transferring it from arteries to veins.
• Countercurrent exchangers are efficient because they maintain a gradients.
• Small differences in heat along the exchanger form a large overall temperature gradient.