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Introduction to College Biology - Lecture 1 (Ch. 1) Vocabulary Flashcards

What is Biology? Key Themes

  • Biology is the science of life. All living organisms share several key properties:
    • Order
    • Sensitivity (response to stimuli)
    • Reproduction
    • Adaptation to their environment (Evolutionary adaptation)
    • Growth and development
    • Regulation (maintaining a stable internal environment, i.e., homeostasis)
    • Use energy
  • Important distinction: Evolutionary adaptation occurs over generations and is not done by every individual organism.
    • Question to consider: Does every individual show adaptation? No. Adaptation is population- or species-level over time.
  • Organisms must respond to their environment; this is different from adaptation, which is a long-term population change.
  • Species-level concept: You can discuss life at the species level (e.g., what makes a species alive across generations) rather than focusing on a single individual.
  • A memory-friendly hierarchy helps organize life from large to small as:
    • Biosphere → Ecosystems → Populations → Communities → Organ Systems and Organs → Tissues → Cells → Organelles → Molecules and Atoms
    • This is often summarized in a mnemonic that moves from big to small (Big to Small): Biosphere, Ecosystems, Populations, Communities, Organ Systems and Organs, Tissues, Cells, Organelles, Molecules and Atoms.
  • The study of biology is broad and interdisciplinary, with subdisciplines such as molecular biology, microbiology, neurobiology, zoology, and botany.

Hierarchy of Life (Big to Small)

  • Key levels (from largest to smallest):
    • Biosphere: all life on Earth; Earth as an ecosystem
    • Ecosystems: living and non-living components interacting
    • Populations: a group of individuals of one species
    • Communities: all interacting populations in an ecosystem
    • Organ Systems and Organs: groups of organs that work together; organs are composed of tissues
    • Tissues: an integrated group of similar cells that work together
    • Cells: the basic unit of life; the smallest unit capable of life processes; enclosed by a membrane that regulates passage of materials
    • Organelles: specialized structures within cells
    • Molecules and Atoms: atoms are fundamental units of matter; molecules are groups of atoms bonded together
  • At the cellular level, organisms are organized into cells with membranes; the cell is the fundamental unit of life (prokaryotic vs eukaryotic distinction discussed in figures showing nucleoid region vs nucleus and the presence/absence of membrane-bound organelles).
  • Figures illustrate units from nucleoid region and organelles to nucleus, to the larger hierarchy (Molecule → Atom; Nucleus; Cells; Tissue; Organs; Organ Systems; Organisms; Populations; Communities; Ecosystems; Biosphere).

The Cell: Structure & Function

  • The cell is the smallest unit of organization that can perform all life activities.
  • Every cell is enclosed by a membrane that regulates passage of materials between the cell and its environment.
  • Cells are the basic unit of life and the site of essential life processes; organelles perform specific cellular functions.
  • The cell’s structure is closely tied to its function (structure–function relationship).

Major Course Theme: Structure & Function

  • At each level of the biological hierarchy, there is a correlation between structure and function.
  • Analyzing a biological structure gives clues about what it does and how it works (and vice versa).

Darwin’s Beaks and Adaptation (Bird Beak Morphology as a Case Study)

  • Examining birds’ beaks reveals main coordinated changes in skull/beak shape among different species:
    • Large ground finch (Geospiza magnirostris)
    • Nihoa finch (Telespiza ultima)
    • Green warbler-finch (Certhidea olivacea)
    • Oahu creeper (Paroreomyza maculata)
  • Beak region vs skull region differences illustrate adaptations to feeding strategies and environments.

Energy: How Living Things Use Energy

  • Living things take in energy and use it for maintenance and growth.
  • Energy sources mentioned: ATP and glucose, illustrating cellular energy currency and metabolism.

Adaptation and Variation

  • Adaptations are traits that give an organism an advantage in a particular environment.
  • Variation among individuals within a population is important for a healthy species.
  • Adaptation is slow and occurs across generations; individuals do not “become” adapted in real-time.

Respond to Stimuli

  • Living things respond to environmental stimuli.
  • Examples include plants and animals responding to their surroundings; a video example is noted for demonstration.
  • The speed of response is emphasized as an important trait of life.

Growth & Development

  • Growth can occur by cell division (the number of cells increases).
  • Growth can also occur by cell enlargement (increase in the size of a cell).
  • Cells grow to a certain size and then divide as part of development and maintenance.

Homeostasis and Regulation

  • Homeostasis: the ability of an organism to maintain a stable internal environment (steady state) despite environmental changes.
  • Regulation examples include maintaining:
    • Temperature
    • pH
    • CO2 levels
    • Blood pressure
    • Water balance
    • Blood sugar
  • Homeostasis is a key mechanism that supports survival in changing environments.

Reproduction: A Species-Level Concept

  • All living things reproduce via:
    • Asexual reproduction: offspring without gamete fusion
    • Sexual reproduction: offspring produced by the joining of sex cells (gametes)
  • Reproduction is essential for species persistence but is not necessary for the survival of any single organism.

What is Alive? Core Criteria (Overarching Summary)

  • Living things are defined by a set of criteria:
    1. Organization
    2. Respond to stimuli
    3. Reproduce
    4. Adapt
    5. Grow & Develop
    6. Regulate a stable internal environment using homeostasis
    7. Use energy
  • Note on exceptions and edge cases:
    • A mule is alive (an individual) but is not a species on its own.
    • A virus is NOT technically alive by several criteria.

The Word Roots of Biology

  • Bio- means life; -logy means the study of.
  • Ancient Greek root hierarchy: hierarkhia (hierarchy) means “rule of a high priest.”
  • Not Biology: the study of life is Biology; some terms reflect living (Biotic) vs non-living or stasis (Homeo) concepts.

The Cell: Prokaryotes vs Eukaryotes (Key Distinctions)

  • Prokaryotic cells (e.g., bacteria) vs Eukaryotic cells (e.g., plant/animal cells) differ in complexity and presence of a nucleus and organelles.
  • Prokaryotes have a nucleoid region where DNA is concentrated and lack membrane-bound organelles.
  • Eukaryotes have a nucleus enclosed by a membrane and numerous organelles that perform specialized functions.

The Hierarchy of Life: Detailed Diagrams and Definitions

  • Figure breakdowns illustrate the progression from atoms and molecules to cells, organelles, tissues, organs, organ systems, organisms, populations, communities, ecosystems, and the biosphere.
  • Nucleus vs Nucleoid region: the nucleus is a membrane-bound organelle in eukaryotes; prokaryotes lack such a membrane-bound nucleus.

Why Biology is Interdisciplinary and Practical

  • Biology’s reach extends to molecular biology, microbiology, neurobiology, zoology, botany, and beyond.
  • Real-world relevance includes understanding health, disease, ecosystems, and the sustainable management of biological resources.

Course Logistics and Study Tips (Unspoken Rules for College)

  • You are responsible for your own assignments; keep records of verbal agreements and due dates with professors to prevent misunderstandings.
  • Seek extra credit and study materials when available; complete extra credit opportunities.
  • If extensions are needed, ask early; check the syllabus for rules (e.g., doctor’s notes, DSPS accommodations).
  • DSPS (Disability Support Programs and Services) can help obtain accommodations for assignments and exams.
  • If you miss a deadline, ask about partial credit options; some points are better than zero.
  • Attend office hours; building a relationship with the professor can help with recommendations and learning.
  • Form study groups; professors can help facilitate group work.
  • When emailing about assignments, include specific questions and show your work; provide your attempted answer to demonstrate effort.

Checklists and Quick References

  • Check your course fit:
    • Allied health track (nursing, medical assistant, dental hygiene) often prerequisites BIOS 41; this class may count toward prerequisites for anatomy, physiology, microbiology.
    • Biology major or pre-professional tracks may require BIOS 21A/21B for a four-year biology degree or medical/veterinary school.
    • GE credit seekers may take BIOS 1 if no other biology coursework is planned.
    • When uncertain, consult a counselor to enroll in the correct biology course.

Visual Aids Mentioned

  • Figure 1.0: Biology = The Study of Life; science becoming interdisciplinary by combining multiple fields.
  • Figures 1.2-3 and variations illustrate the hierarchical relationships (Biosphere, Ecosystems, Populations, Communities, Organisms, Organ Systems, Tissues, Cells, Organelles, Molecules, Atoms, Nucleus).
  • Figure 1.3 emphasizes the Biosphere and ecosystem context with numbered levels.
  • Figure 1.4 shows differences between nucleoid region and nucleus, illustrating prokaryotic vs eukaryotic cells.

Closing Takeaways

  • Biology connects structure and function at every level of organization.
  • Life is characterized by organized complexity, energy use, responsiveness, growth, development, regulation, reproduction, and adaptation over generations.
  • The study of life blends empirical evidence, mathematical reasoning, and ethical/philosophical considerations about what constitutes life and how we apply biological knowledge in society.