Physiology and Scientific Method MCQs

• These are study notes on science and biology

Scientific Method

• The scientific method includes observation, question formulation, hypothesis, experiment, data analysis, conclusion, and replication.

Experimental Variables

• A control group is a baseline group without the treatment.
• Controlled variables are factors kept constant during an experiment.
• The independent variable is the factor that is changed in an experiment.
• The dependent variable is the outcome that is measured in an experiment.

Experiment Replication

• Replication in an experiment is important because it ensures reliability and repeatability by reducing random errors.

Characteristics of Life

• Something is considered alive if it exhibits organization, metabolism, homeostasis, growth, reproduction, response to stimuli, and adaptation.

Scientific Theory vs. Fact

• A scientific theory is a well-supported explanation of facts.
• A scientific fact is an observed, confirmed phenomenon.

Influences on Darwin

• Darwin's early influences included Malthus' ideas on population growth and Lyell's work in geology.
• Darwin's own natural observations also heavily influenced him.

Requirements for Natural Selection

• Natural selection requires variation, heredity, and differential survival/reproduction.
• These factors allow advantageous traits to be selected.

Convergent vs. Divergent Evolution

• Convergent evolution happens when similar environments produce similar traits in unrelated species.
• Divergent evolution occurs when related species adapt differently to different environments.

Allopatric Speciation

• Allopatric speciation happens because of geographic isolation.
• Types include vicariance, where barriers form, and peripatric, involving small, isolated populations.

Sympatric Speciation

• Sympatric speciation is speciation without geographic isolation.
• Examples include polyploidy, especially in plants, and sexual selection.

Evolutionary Forces in Populations

• Mutation introduces new genetic variation.
• Gene flow moves alleles between populations.
• Genetic drift involves random changes in allele frequencies.
• Natural selection favors beneficial traits.
• Sexual selection favors traits that improve mating success.
• Non-random mating alters allele frequencies by mate choice.

Evidence for Evolution

• Evidence supporting evolution includes fossil records, comparative anatomy, embryology, molecular biology, and biogeography.
• Observed evolutionary changes also provide evidence.

Evolutionary Relationships

• Evolutionary relationships are depicted with phylogenetic trees or cladograms.

Levels of Ecology

• The four levels of ecology are individual, population, community, and ecosystem.

Offspring and Parental Care

• High parental care usually means fewer, well-invested offspring.
• Low parental care means many offspring with less energy invested per individual.

Population Growth Factors

• Population growth occurs when births and immigration exceed deaths and emigration.
• Population decline happens when deaths and emigration exceed births and immigration.

Population Age Structures

• Rapidly growing countries have a pyramid-shaped age structure with many young individuals.
• Slowly growing countries have a more column-like age distribution.
• Zero-growth countries have balanced age groups with a narrower base.

Innate Behaviors

• Types of innate behaviors in a population are instincts, fixed action patterns, and reflexes.

Predator and Prey Evolution

• Predators evolve speed, stealth, and specialized senses.
• Prey evolve camouflage, vigilance, and rapid escape responses.

Active vs. Passive Defense Strategies

• Active defense strategies include behaviors like fleeing, fighting, or aggressive mimicry.
• Passive defense strategies include camouflage, mimicry, or physical defenses like armor or spines.

Symbiosis Types

• Symbiosis is a close interaction between species.
• Mutualism: Both species benefit.
• Commensalism: One species benefits, and the other is unaffected.
• Parasitism: One species benefits at the expense of the other.

Human Impact on Biogeochemical Cycles

• Human activities like deforestation, pollution, and burning fossil fuels disrupt nutrient cycles.
• This leads to climate change, eutrophication, and biodiversity loss.

Factors Influencing Distribution

• The distribution of living things depends on climate, geography, and resource availability.
• Endemic species are often found in isolated or unique habitats.

Species Roles

• Pioneer species are the first colonizers that initiate ecosystem development.
• Foundational species create habitat structure.
• Keystone species have a disproportionately large impact on ecosystem function.

Thermodynamics and Food Chains

• The 2nd Law of Thermodynamics relates to food chains because energy is lost as heat at each trophic level.
• This reduces the energy available to higher trophic levels.

Trophic Levels

• Producers: Plants convert energy. Examples: trees, algae.
• Primary consumers: Herbivores. Examples: rabbits, insects.
• Secondary consumers: Carnivores eating herbivores. Examples: frogs, small birds.
• Tertiary consumers: Top predators. Examples: hawks, wolves.
• Decomposers: Recycle nutrients. Examples: fungi, bacteria.

Current Threats to Biodiversity

• Threats include habitat destruction, climate change, invasive species, pollution, and overexploitation.

Biome Trends

• Tropical regions near the equator are warm and highly biodiverse.
• Higher latitudes are cooler with less diversity.

Invertebrates vs. Vertebrates

• Invertebrates lack a backbone and usually have simpler body plans.
• Vertebrates have a backbone and complex organ systems.

Endotherms vs. Ectotherms

• Endotherms regulate body temperature internally (mammals, birds).
• Ectotherms rely on external heat sources (reptiles, amphibians, fish).

External vs. Internal Fertilization

• External fertilization produces many gametes but carries the risk of lower success due to environmental exposure.
• Internal fertilization offers protection and higher fertilization rates, but fewer gametes are produced.

Sessile vs. Motile

• Sessile organisms save energy and resources but cannot escape threats.
• Motile organisms can move to avoid danger or seek resources but use more energy.

Closed vs. Open Circulatory Systems

• Closed systems have blood flowing within vessels, are more efficient, and are seen in vertebrates. An open circulatory system has blood that bathes organs directly, is simpler, and found in many invertebrates

Fish Adaptations

• Fish are adapted to living aquatically through gills for extracting oxygen, streamlined bodies, and fins for maneuverability.

Amphibian Adaptations

• Amphibians are adapted to living in moist environments because they possess permeable skin for gas exchange and need moisture to prevent dehydration.

Reptile Adaptations

• Reptiles are adapted to live terrestrially with scales that minimize water loss.
• They use external heat to regulate body temperature.

Bird Adaptations

• Birds are adapted to flight with lightweight bones, strong flight muscles, aerodynamic feathers, and efficient respiratory systems.

Marine Mammal Adaptations

• Marine mammals are adapted to the ocean with streamlined bodies, blubber for insulation, modified limbs for swimming, and specialized respiratory adaptations.

Human Body Systems

• The systems within the human body (circulatory, respiratory, digestive, nervous, endocrine, musculoskeletal, immune, etc.) work together to maintain homeostasis and support life functions.

Bioenergetics

• Bioenergetics studies energy flow and transformation in living systems, particularly cellular metabolism.

Steps of Food Processing

• The four steps of processing food are ingestion, digestion, absorption, and assimilation/excretion.

ATP

• ATP (adenosine triphosphate) is the primary molecule for storing and transferring energy in cells.

Neuron Communication

• Neurons communicate through electrical impulses (action potentials) and chemical signals (neurotransmitters) across synapses.

The Five Senses

• The five senses being sight, hearing, taste, smell, and touch.

Sensory Stimuli Processing

• The three steps for processing sensory stimuli are reception (detection), transduction (conversion to nerve signals), and perception (brain interpretation).

Hormones and Their Roles

• Cortisol manages stress and increases blood glucose.
• Serotonin regulates mood.
• Oxytocin promotes bonding and aids in childbirth.
• Dopamine is involved in reward and motivation.
• Estrogen governs female reproductive development.
• Testosterone governs male reproductive development.
• Insulin regulates blood sugar levels.
• HGH stimulates growth and cell reproduction.
• Epinephrine/Adrenaline triggers fight-or-flight responses.

Bone Repair Stages

• Bone repair occurs in four stages: hematoma formation, fibrocartilaginous callus formation, bony callus formation, and bone remodeling.

Oxygen Pathway

• Oxygen travels into the lungs, diffuses into the bloodstream via alveoli, is transported by hemoglobin.
• Carbon dioxide is carried back and exhaled.

Respiratory System Protection

• Protective mechanisms in the human respiratory system are mucus and cilia to trap and expel particles.
• Immune cells (like alveolar macrophages) help defend against pathogens.

Carbon Monoxide Poisoning

• CO binds to hemoglobin more effectively than oxygen, reducing oxygen delivery to tissues.

Hemoglobin's Role

• Hemoglobin transports oxygen from the lungs to tissues and carries carbon dioxide back to the lungs.

Immune Systems

• The innate immune system has non-specific, immediate defenses (e.g., skin, phagocytes).
• The adaptive immune system has specific, memory-based responses (e.g., T cells, B cells).

Antibodies

• Antibodies are proteins produced by B cells that bind to specific antigens.
• They neutralize pathogens or mark them for destruction.

Fevers

• A fever boosts immune function and creates an environment less favorable for bacterial growth during a bacterial infection.

Multiple-choice questions covering human physiology, the immune system, and the scientific method. Topics include bone repair, hemoglobin function, carbon monoxide poisoning, fever response, adaptive immunity, and experimental design in plant biology.