Unit 0: Cell Types and Kingdoms

Practical Guidelines and Formative Expectations

• General Formatting Requirements:

  • Name Inclusion: Always include both first name and last name, along with the class hour, on submitted activities.

  • Work Space Utilization: Use all provided space completely when completing diagrams, drawings, and graphs.

  • Written Response Strategy: Concise written answers are preferred over overly lengthy descriptions; providing more words is not always beneficial.

  • Pre-Submission Verification: Review all work thoroughly before final submission. Pay special attention to bold terms.

  • Completeness: Do not leave any questions or tasks blank. Formative assignments serve as critical skill practice and should not be delayed until summative assessments.

• Targeted Study Questions:

  • Shared Plant Kingdom Characteristics: Identification of all essential biological traits shared across members of the Plant kingdom.

  • Wildflower Variation: Explanation of the underlying causes responsible for biological variation among wildflower species.

Fundamentals of Cell Theory

• The Cell Theory Overview:

  • The Cell Theory serves as the foundational framework summarizing scientific knowledge regarding cells and living organisms.

• Core Tenets of Cell Theory:

  • Tenet 1: The cell is the smallest piece of life.

  • Tenet 2: All living things are made of cells.

  • Tenet 3: Cells come from other cells.

Basic Universal Cell Structures

• Universal Components:

  • ALL cells contain three fundamental structural parts regardless of organism type or complexity.

• 1. Control Center:

  • Function: Regulates and controls all activities occurring within the cell.

  • Molecular Composition: Contains genetic material in the form of DNA or RNA.

• 2. Cytoplasm:

  • Definition: The interior volume of the cell encompassing fluid, internal structures, and the cytoskeleton.

  • Scope: Comprises all internal cell contents with the exception of the genetic material.

• 3. Cell Membrane (Plasma Membrane):

  • Definition: A lipid-based membrane surrounding EVERY cell.

  • Permeability Control: Serves as the selective barrier; anything moving into or out of the cell must pass through this membrane.

Cell Structure and Function Diversity

• Principle of Cell Diversity:

  • Biological principle: Cell shape directly reflects cell function.

• Examples of Shape-Function Adaptation:

  • Blood Cells: Characterized by a round and flexible structure, enabling smooth passage and travel through narrow capillaries.

  • Plant Cells: Encased by rigid cell walls that provide structural framework and upright support for the plant body.

  • Nerve Cells: Formed with long and skinny cellular extensions tailored for transmitting neural messages across distances.

Key Biological Definitions and Kingdom Characteristics

• Cellular Composition:

  • Unicellular: Organisms composed of only a single cell. Examples include Amoeba, Bacteria, and Paramoecium.

  • Multicellular: Organisms consisting of many specialized cells working in conjunction. Examples include Plants and Animals.

• Outer Structural Boundaries:

  • Cell Wall: A rigid exterior layer surrounding certain cells, constructed primarily from structural carbohydrates.

  • Cell Membrane: The universal outer bounding layer found in all cells, composed primarily of lipids.

• Energy Acquisition Strategies:

  • Autotrophic (Producers): Organisms that synthesize their own energy and organic molecules from inorganic sources via photosynthesis or chemosynthesis. Examples include Plants, Algae, and some bacteria.

  • Heterotrophic (Consumers): Organisms that acquire energy and organic molecules by ingesting or absorbing other organisms to obtain essential proteins and chemical energy. Examples include Animals, Fungi, and most bacteria.

• Internal Subcellular Compartmentalization:

  • Organelles: Specialized, membrane-bound internal structures contained within eukaryotic cells.

  • Microenvironment Control: Membrane encapsulation allows distinct internal microenvironments (such as specific $\text{pH}$ levels) optimized for specific cellular biochemical processes.

  • Key Examples: Nucleus, Mitochondria, Chloroplasts.

• Cell Organization Types:

  • Prokaryotic: Cells lacking a membrane-bound nucleus and missing other membrane-bound organelles.

  • Eukaryotic: Cells containing a distinct membrane-enclosed nucleus alongside specialized organelles.

Biological Classification and Taxonomic Hierarchy

• Systemic Taxonomic Structure:

  • Classification Logic: All living organisms are classified into exactly one of six primary Kingdoms. Moving down each progressive level of classification divides organisms into increasingly specific groupings.

  • Hierarchical Example (Kingdom to Class): Kingdom Animalia is subdivided into multiple phyla (singular: phylum); Phylum Chordata is further subdivided into distinct classes including mammals, reptiles, and amphibians.

• Levels of Biological Classification:

  • Level 1: Domain

  • Level 2: Kingdom

  • Level 3: Phylum

  • Level 4: Class

  • Level 5: Order

  • Level 6: Family

  • Level 7: Genus

  • Level 8: Species

• Biological Species Concept:

  • Definition: A species is defined as a population of organisms capable of successfully reproducing only with members of its own species.

• Comparative Taxonomic Profiles:

  • Human Taxonomic Profile:

  • Domain: Eukaryota

  • Kingdom: Animalia

  • Phylum: Chordata

  • Class: Mammalia

  • Order: Primates

  • Family: Hominidae

  • Genus: Homo

  • Species: Homo sapiens

  • Grizzly Bear Taxonomic Profile:

  • Kingdom: Animalia

  • Phylum: Chordata

  • Class: Mammalia

  • Order: Carnivora

  • Family: Ursidae

  • Genus: Ursus

  • Species: Ursus arctos

The Six Kingdoms of Life

• 1. Kingdom Archaebacteria (Archaea):

  • Common Term: Ancient bacteria.

  • Cell Type: Prokaryotic (lacks a membrane-bound nucleus).

  • Cellularity: Unicellular (single-celled).

  • Scale: Microscopic.

  • Ecological Niche: Extremophiles that thrive in extreme environment conditions (such as high heat, low oxygen levels, severe cold, or complete darkness).

  • Specialized Extremophile Examples:

  • Thermophiles: Heat-tolerant organisms located in environments like the Yellowstone Nat'l Park Hot Springs.

  • Halophiles: Salt-tolerant organisms adapted to high salinity and low oxygen conditions, such as those found in the Dead Sea.

• 2. Kingdom Eubacteria:

  • Common Term: Common bacteria.

  • Cell Type: Prokaryotic.

  • Cellularity: Unicellular.

  • Scale: Microscopic.

  • Distribution: Ubiquitous organisms found on, inside, and surrounding human and terrestrial environments.

  • Representative Example: E. coli.

• 3. Kingdom Protista (Protists):

  • Cell Type: Eukaryotic.

  • Cellularity: Unicellular.

  • Energy Strategies: Dual pathways available across the kingdom—Autotrophic (utilizing photosynthesis to produce food) or Heterotrophic (ingesting food).

  • Motility Mechanisms: Capable of self-propulsion using Flagella, Cilia, or Pseudopods.

  • Morphology & Traits: Exhibits diverse body shapes; shares functional and structural similarities with both plant and animal cells.

  • Outer Boundary: Bound externally by a cell membrane.

• 4. Kingdom Fungi:

  • Cell Type: Eukaryotic.

  • Cellularity: Unicellular (e.g., Yeast) or Multicellular (e.g., Mushrooms, Molds).

  • Cell Wall Composition: Contains a rigid cell wall composed of Chitin (the same structural polysaccharide forming insect exoskeletons).

  • Motility Status: Sessile (incapable of locomotion).

  • Nutritional Mode: Heterotrophic; acquires nutrients specifically through absorption.

  • Primary Examples: Mushrooms, Molds, Yeast.

• 5. Kingdom Plant (Plantae):

  • Cell Type: Eukaryotic.

  • Cellularity: Multicellular (composed of complex organ systems and numerous cells).

  • Energy Strategy: Autotrophic (synthesizes food internally; contains specialized chloroplasts for photosynthesis).

  • Motility Status: Sessile (stationary, does not move).

  • Cell Wall Composition: Outer cell wall composed of Cellulose.

• 6. Kingdom Animalia:

  • Cell Type: Eukaryotic.

  • Cellularity: Multicellular.

  • Energy Strategy: Heterotrophic (must ingest external food sources).

  • Outer Boundary: Lacks cell walls entirely; enclosed exclusively by a flexible cell membrane.

  • Motility: Capable of independent self-movement.

  • Major Structural Subdivisions:

  • Invertebrates: Animals lacking a vertebral column / backbone (may possess supportive external exoskeletons).

  • Vertebrates: Animals possessing a backbone (skeletal structure internalized beneath skin as an endoskeleton).

Comprehensive Comparison Matrix of Kingdoms

• Archaebacteria:

  • Cell Type: Prokaryotic

  • Cellularity: Unicellular (Microscopic)

  • Location of DNA: Cytoplasm (Nucleoid region; no nuclear membrane)

  • Energy Strategy: Autotrophic or Heterotrophic

  • Outer Boundary: Both Cell Membrane and Cell Wall

  • Primary Examples: Thermophiles, Halophiles

• Eubacteria:

  • Cell Type: Prokaryotic

  • Cellularity: Unicellular (Microscopic)

  • Location of DNA: Cytoplasm (Nucleoid region; no nuclear membrane)

  • Energy Strategy: Autotrophic or Heterotrophic

  • Outer Boundary: Both Cell Membrane and Cell Wall

  • Primary Example: E. coli

• Protista:

  • Cell Type: Eukaryotic

  • Cellularity: Unicellular

  • Location of DNA: Nucleus (Membrane-bound)

  • Energy Strategy: Autotrophic or Heterotrophic

  • Outer Boundary: Cell Membrane (some forms possess walls)

  • Primary Examples: Amoeba, Paramoecium, Euglena

• Fungi:

  • Cell Type: Eukaryotic

  • Cellularity: Unicellular or Multicellular

  • Location of DNA: Nucleus (Membrane-bound)

  • Energy Strategy: Heterotrophic (Absorptive)

  • Outer Boundary: Both Cell Membrane and Cell Wall (Chitin)

  • Primary Examples: Mushrooms, Molds, Yeast

• Plants:

  • Cell Type: Eukaryotic

  • Cellularity: Multicellular

  • Location of DNA: Nucleus (Membrane-bound)

  • Energy Strategy: Autotrophic (Photosynthetic)

  • Outer Boundary: Both Cell Membrane and Cell Wall (Cellulose)

  • Primary Examples: Trees, Flowers, Ferns, Mosses

• Animals:

  • Cell Type: Eukaryotic

  • Cellularity: Multicellular

  • Location of DNA: Nucleus (Membrane-bound)

  • Energy Strategy: Heterotrophic (Ingestive)

  • Outer Boundary: Cell Membrane only (No cell wall)

  • Primary Examples: Invertebrates (Spiders, Snails), Vertebrates (Bears, Humans, Cats)