Asexual Reproduction Methods

• Notes for Earth and Life Science, 2nd Quarter Examination

Introduction to Life

• Order: All living organisms adhere to a biological hierarchy within the biosphere
• Reproduction: The capacity to produce new individuals through sexual or asexual means
• Response to Stimuli: Sensitivity to changes in the environment
• Homeostasis: Maintaining internal equilibrium despite external changes
• Growth is an increase in an organism's size and mass over time
• Development signifies the progression of changes in structure, function, and complexity of an organism
• Adaptation: Evolving to adjust to or fit into a changing environment
• Metabolism: The process of building up and breaking down complex molecules in the body

Theories on the Origin of Life

• Special/Divine Creation Theory: all things, including the universe, Earth, and organisms, came to be by a Supreme being, or "God"
  • Rejected due to lack of scientific evidence and reliance on faith
• Panspermia: Life is distributed throughout the universe and can travel from planet to planet via meteors and asteroids
  • Rejected because Earth is the only known planet to harbor life
  • Organisms are not able to travel between planets via meteors
• Spontaneous Generation: Life can originate from non-life (abiogenesis)
• Biogenetic Theory/Biogenesis: Life originates from pre-existing life

Unifying Theme in the Study of Life

• Cell Theory: all organisms are composed of cells

  • All living things are made of cells
  • The cell is the basic unit of structure and function in organisms
  • Cells originate from pre-existing cells

• Gene Theory: Living organisms pass on traits or characteristics through genes found within their DNA

• Structure and Function: The structure of body dictates its function

  • Homologous Structures: Same structure but different function
  • Analogous Structures: same function but different structures

• Evolutionary Theory: Organisms descend from a common ancestor and evolve due to environmental changes

Perpetuation of Life

• Reproduction is a biological process where new individuals are produced by a parent
• Asexual Reproduction: Creation of a new individual from a single parent
  • It does not require the fusion of gamete cells
  • Results in the formation of a clone (a natural process)
  • Advantages: Faster, requires less energy, retains useful characteristics, effective for isolated organisms
  • Disadvantages: No variation, susceptible to disease, competition for resources
• Binary Fission: A parent cell divides into two new daughter cells of equal size
  • Examples: Paramecium, Amoeba, E. coli
• Budding: A new individual forms from an outgrowth of the parent's body
  • Examples: Yeast cell, hydra, corals
• Fragmentation: An organism breaks into fragments, each developing into a fully-formed individual
  • Example: Planarian worm
• Regeneration allows organisms to regrow lost or damaged body parts
  • For healing, repair, and replacement of lost body parts
  • Examples: Sea stars, lizards, salamanders, axolotl
• Parthenogenesis: A female produces offspring from an unfertilized egg
  • Unfertilized eggs develop into female individuals without fertilization by sperm
  • Examples: Honeybees, Komodo dragons
• Sexual Reproduction: Involves two parents with different sex characteristics
  • Requires the fusion of sperm and egg cells
  • Advantages: Variation of species, increased adaptability, transfer of acquired characteristics
  • Disadvantages: Genetic mutation, takes longer, fails if organism is isolated
• Internal Fertilization: Fusion of gamete cells happens inside the female's body
  • Examples: Humans, tigers, monkeys, cows, goats, reptiles
• External Fertilization: Fusion of gamete cells happens outside the female's body or in the environment
  • The zygote develops outside the female body
  • Examples: Frog eggs, salmon eggs

Genes and Genetic Engineering

• Genes: Units of heredity transferred from parent to offspring
• Punnett Square: Used to predict all possible outcomes of a genetic cross between two individuals with known genotypes
• Genetic Engineering: Altering, modifying, or manipulating an organism's genes
• Selective Breeding: Intentionally mating organisms with desirable traits to produce offspring with those traits
  • Termed "artificial selection"
  • Examples: Cows, plants, dogs, cats
• Hybridization: Breeding individuals from different species, genera, or populations with genetically different characteristics
  • Examples: Mule, liger, tigon, zorse, wholphin
• Cloning: Creating genetically identical individuals or exact copies of an organism, naturally or artificially
  • Natural: Asexual reproduction and mitotic cell division
  • Dolly the sheep: the first mammal to be cloned from an adult somatic cell using somatic cell nuclear transfer (SCNT)
• DNA Recombination: Artificially creating DNA sequences by combining genetic material from different organisms in a lab
  • Alters and modifies the organism's genetic code
  • For creating Transgenic organisms, known as GMOs
• Genetically Modified Organism (GMO): Organisms (plants, animals, microorganisms) that have had their DNA manipulated in a lab through genetic engineering
  • Examples: Apples, potatoes, papayas, alfalfa, soybeans, cotton, sugar beets, summer squash
• Advantages of Genetic Engineering and GMO
  • Improve human life
  • Maintain environment through bioremediation
  • Profit source
  • Conserve endangered species
  • Create resistant crops with longer shelf life and improved nutrients
• Disadvantages of Genetic Engineering and GMO
  • Overly mutated genes
  • Gene pollution
  • New diseases and antibiotic resistance may develop
  • Reduced variation in gene pool
  • Allergic reactions in populations may occur
  • Unethical

Organ Systems

• Integumentary System: Hair, nails, skin
  • Covers internal organs
  • Provides external protection
  • Receives external stimuli
• Skeletal System: Bones and joints
  • Protects and supports body organs
  • Provides framework/movement
  • Produces new blood cells (hematopoiesis)
• Muscular System: Provides movement
  • Maintains posture and facial expression
  • Produces heat
• Nervous System: Brain, nerves, and spinal cord
  • Controls organs/body systems through neurons
  • Analyzes information and provides instructions
• Reproductive System: Eliminates waste and procreation
• Cardiovascular System: Heart, blood, and blood vessels
  • Pumps oxygenated blood/nutrients
  • Removes carbon dioxide
• Digestive System: Breaks down food into absorbable units
  • Eliminates useless materials (fecal route)
• Respiratory System: Nose, lungs, trachea, and larynx
  • Provides oxygen
  • Disposes of carbon dioxide
  • Regulates blood pH
• Urinary System: Eliminates waste, regulates water/electrolytes, and balances blood pH.
  • Organs include kidneys, ureter, urinary bladder, and urethra
• Endocrine System: Secretes hormones
  • Crucial for growth, reproduction, and metabolism
  • Maintains internal balance
• Lymphatic System: Protects against pathogens
  • Activates immune response
  • Distinguishes/digests foreign substances

Processes of Evolution

• Evolution is the gradual change in population species over time
• Adaptive Radiation: Finches, a phenomenon observed by Charles Darwin on the Galápagos Islands.
• Ancestor Finch: Image begins with a common ancestral finch species with similar habitat and eating habits
• Natural Selection: Individuals with beak shapes/sizes adapted to food sources were favored.
• Divergence into Specialized Forms through evolution of different beak types
  • Insect-eating with a narrow, pointed beak
  • Woodpecker-type of insect eating with a beak adapted for extracting insects
  • Seed-eating with thicker beak for cracking seeds
• Jean Baptiste Lamarck: "Theory of use and disuse
  • Species change as a result of how often they use body parts
• Carolus Linnaeus pioneered Taxonomy and named the father of taxonomy
  • Developed the "binomial nomenclature"
• Charles Darwin pioneered evolutionary theory
  • Species gradually evolve through natural selection
• Natural Selection: Species best suited for their environment have a greater chance of survival
  • "Survival of the fittest"
• Gene Flow: Movement of genes increasing gene diversity
  • Can occur through migration, pollination, and hybridization
• Genetic Drift: Frequency of certain traits in a population changes due to random events (genetic mutations, mating, or migration)
• Mutation: Change in genetic makeup caused by factors like mutagens

This quiz assesses the understanding of various asexual reproduction methods, including binary fission, budding, fragmentation, and parthenogenesis. It explores how different organisms utilize these methods to reproduce and adapt to their environments.