25-26 Semester 1 Final Exam Study Guide (HHS)

25-26 Semester 1 Final Exam Study Guide (HHS)

Unit: Africa & Elephant Storylines

### Individual (Paper) for Final Exam on December 17 & 18

Chains, Food Webs & Species Interactions

  1. Similarities Between Food Chains and Food Webs

    • Both illustrate how energy flows through an ecosystem between organisms.

    • Both depict the flow of energy and matter within ecological relationships.

  2. Differences Between Food Chains and Food Webs

    • Food Chain:

      • Represents a single pathway through which energy and nutrients move.

    • Food Web:

      • More complex; shows interconnections and multiple pathways of energy flow.

  3. Example of Food Chain and Food Web:

    • Food Chain Example:

      • Grass -> Grasshopper -> Frog -> Snake -> Hawk

    • Food Web Example:

      • Interconnections depicted with various species: Grass, Grasshopper, Frog, Snake, Mouse, Hawk.

  4. Impact of Disturbance in a Food Web:

    • Disruptions to one organism can impact the entire web.

    • Effects:

      • Loss of predators can result in prey population explosions.

      • Potential extinction of species due to ecological imbalance.

  5. Energy Pyramid and Trophic Levels:

    • Example arrangement of trophic levels:

      • Producer: Grass (100,000 kcal)

      • Primary Consumer: Grasshopper (10,000 kcal)

      • Secondary Consumer: Snake (1,000 kcal)

      • Tertiary Consumer: Hawk (100 kcal)

    • Note: Energy is lost at each level, adhering to the 10% rule.

  6. The 10% Rule:

    • Only about 10% of energy is transferred from one trophic level to the next.

    • It limits energy availability for top-level predators and empowers bottom-level organisms.

Types of Eaters

  1. Definitions and Examples:

    • Carnivore:

      • Definition: Organism that eats only animals.

      • Example: Fox, Wolf, Lion, Hawk

    • Herbivore:

      • Definition: Organism that eats only plants.

      • Example: Zebra, Horse, Cow

    • Omnivore:

      • Definition: Organism that eats both plants and animals.

      • Example: Raccoon, Pig, Dog

    • Detritivore:

      • Definition: Organism that eats dead organisms.

      • Example: Beetles, Crabs, Termites

Carrying Capacity & Limiting Factors

  1. Carrying Capacity:

    • Definition: The maximum population size of a species that the environment can sustain.

    • Effects of exceeding carrying capacity:

      • Increased competition for resources, higher death rates, potential population crash.

  2. Limiting Factors:

    • Definition: Any resource or condition that restricts the growth of a population.

    • Role of limiting factors: Helps to balance population size and keeps it at or below carrying capacity.

  3. Abiotic vs. Biotic Factors:

    • Abiotic Factors:

      • Definition: Non-living components of an ecosystem.

      • Examples: Temperature, Water Availability, Sunlight, Oxygen

    • Biotic Factors:

      • Definition: Living components of an ecosystem.

      • Examples: Competition for food, Mates, Space, Predation

  4. Carrying Capacity on Graph Example:

    • The carrying capacity is indicated at 100, the highest level before a decline due to competition resulting in a population crash.

Mitosis & Levels of Organization

  1. Stages of the Cell Cycle:

    • G1 Phase:

      • Cell undergoes initial growth.

    • S Phase:

      • Cell duplicates its entire DNA.

    • G2 Phase:

      • Cell continues to grow and condense DNA into chromosomes.

  2. Process of Mitosis:

    • Stages of Mitosis:

      • Prophase: Chromatin condenses into chromosomes.

      • Metaphase: Chromosomes align at the cell's equatorial plane.

      • Anaphase: Sister chromatids separate and move to opposite poles.

      • Telophase: Nuclear membranes form around each set of chromosomes.

      • Cytokinesis: Cytoplasm divides to form two identical cells.

  3. Purpose of Mitosis:

    • Mitosis is essential for growth, repair, and producing two genetically identical daughter cells from one parent cell.

  4. **Cells Performing Mitosis:

    • Most frequently: Skin cells

    • Least frequently: Cardiac muscle cells, Neurons

Organization of Living Organisms

  1. Hierarchy from Smallest to Largest:

    • Cell > Tissue > Organ > Organ System > Organism

Photosynthesis

  1. Equation of Photosynthesis:

    • Reactants: Carbon Dioxide (6CO2) and Water (6H2O)

    • Products: Glucose (C6H{12}O6) and Oxygen (6O2)

  2. Cell Type for Photosynthesis:

    • Plant cells with chloroplasts perform photosynthesis.

    • Chloroplasts contain the necessary pigmented organelles that facilitate this process.

  3. Main Product of Photosynthesis:

    • Glucose: Used by organisms to metabolize sugar and release energy.

Cellular Respiration

  1. Equation of Cellular Respiration:

    • Reactants: Sugar (C6H{12}O6) and Oxygen (6O2)

    • Products: Carbon Dioxide (6CO2), Water (6H2O), and ATP

  2. Cell Types Performing Cellular Respiration:

    • All living organisms; occurs in the mitochondria of cells.

  3. Main Product of Cellular Respiration:

    • ATP: Used to convert nutrients into usable energy.

Biogeochemical Cycles (Carbon, Nitrogen & Water Cycles)

  1. Purpose of the Carbon Cycle:

    • To move carbon atoms between the atmosphere and living organisms.

    • Regulates Earth’s temperature and enables food production.

  2. Purpose of the Nitrogen Cycle:

    • To recycle nitrogen and convert atmospheric nitrogen into usable forms for plants.

    • Bacteria play a crucial role in facilitating this conversion.

  3. Purpose of the Water Cycle:

    • To purify, distribute, and cycle Earth's freshwater.

    • Without the water cycle, ecosystems would become unlivable, leading to dire consequences for both plants and animals.

Enzymes

  1. Purpose of Enzymes:

    • Enzymes serve as biological catalysts to speed up biochemical reactions and lower the activation energy required for reactions to occur.

  2. Protein Synthesis:

    • Proteins are comprised of amino acids that undergo a specific folding process during protein synthesis.

    • Misfolded proteins can lead to severe consequences for the organism, including potential death due to malfunctioning proteins.

    • Key takeaway: The shape of a protein determines its function; enzymes modulate metabolic pathways by breaking down or synthesizing nutrients.

    • Proteins are one of the four macromolecules alongside Lipids, Carbohydrates, and Nucleic Acids.