Cell Structure and Function Quiz

Cell Structure and Function

• Cell Theory:

  • All living organisms are made of cells.
  • The cell is the basic unit of life.
  • All cells arise from pre-existing cells.

• Types of Cells:

  • Prokaryotic Cells: Lack a nucleus; simpler structure (e.g., bacteria).
  • Eukaryotic Cells: Contain a nucleus and organelles (e.g., plant and animal cells).

• Organelles:

  • Nucleus: Contains genetic material (DNA).
  • Mitochondria: Powerhouse of the cell; produces ATP.
  • Ribosomes: Protein synthesis.
  • Endoplasmic Reticulum (ER):
    • Rough ER: Studded with ribosomes; synthesizes proteins.
    • Smooth ER: Synthesizes lipids and detoxifies.
  • Golgi Apparatus: Modifies, sorts, and packages proteins.
  • Lysosomes: Digests waste materials.

Genetics

• DNA Structure:

  • Double helix made of nucleotide subunits (adenine, thymine, cytosine, guanine).
  • Antiparallel strands; base pairing (A-T, C-G).

• Gene Expression:

  • Transcription: DNA to mRNA in the nucleus.
  • Translation: mRNA to protein at ribosomes.

• Mendelian Genetics:

  • Laws of Inheritance: Dominant and recessive alleles, segregation, independent assortment.
  • Punnett Squares: Used to predict genotype ratios.

Evolution

• Theory of Evolution:

  • Proposed by Charles Darwin; natural selection is the mechanism for evolution.

• Evidence for Evolution:

  • Fossil records, comparative anatomy, embryology, and molecular biology.

• Speciation:

  • The process through which new species arise, often due to geographic isolation or environmental factors.

Ecology

• Levels of Organization:

  • Organism → Population → Community → Ecosystem → Biome → Biosphere.

• Biogeochemical Cycles:

  • Water cycle, carbon cycle, nitrogen cycle.

• Ecosystem Dynamics:

  • Energy flow (food chains/webs) and nutrient cycling.
  • Trophic levels: producers, primary consumers, secondary consumers, decomposers.

Human Biology

• Body Systems:

  • Nervous System: Central (brain and spinal cord) and peripheral (nerves).
  • Circulatory System: Heart, blood vessels, and blood; transports nutrients and oxygen.
  • Respiratory System: Gas exchange; lungs facilitate oxygen intake and carbon dioxide expulsion.
  • Digestive System: Breaks down food into nutrients; involves the gastrointestinal tract.

• Homeostasis: The maintenance of a stable internal environment despite external changes.

Microbiology

• Microorganisms:

  • Bacteria: Prokaryotic, diverse metabolic pathways.
  • Viruses: Acellular entities; require a host cell to replicate.
  • Fungi: Eukaryotic, decomposers; can be unicellular (yeast) or multicellular (molds).

• Infectious Diseases:

  • Caused by pathogens (bacteria, viruses, fungi, parasites).
  • Transmission methods: direct contact, air, water, vectors.

Plant Biology

• Photosynthesis:

  • Process by which plants convert sunlight into chemical energy (glucose) using chlorophyll.
  • Equation: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂.

• Plant Structure:

  • Roots: Absorb water and nutrients.
  • Stems: Support and transport.
  • Leaves: Main site for photosynthesis.

• Reproductive Strategies:

  • Asexual (e.g., budding, fragmentation).
  • Sexual (involving flowers and seeds).

Animal Behavior

• Innate vs. Learned Behavior:

  • Innate: Genetically programmed actions (e.g., reflexes).
  • Learned: Behavior acquired through experience (e.g., conditioning).

• Social Structures:

  • Communication, mating rituals, and group dynamics in species.

Biotechnology

• Genetic Engineering: Techniques to alter an organism's DNA (e.g., CRISPR).
• Biopharmaceuticals: Use of biological processes for drug development (e.g., insulin production).
• Cloning: Producing genetically identical organisms.

Cell Theory

• All living things are composed of cells
• The cell is the most basic unit of life
• All cells come from pre-existing cells

Cell Types

• Prokaryotic cells lack a nucleus and are simpler in structure
  • Examples: bacteria
• Eukaryotic cells contain a nucleus and have more complex internal structures called organelles
  • Examples: plant and animal cells

Organelles

• Nucleus: Contains genetic material (DNA) and controls cell activities
• Mitochondria: Powerhouse of the cell; responsible for producing energy (ATP)
• Ribosomes: Sites of protein synthesis
• Endoplasmic Reticulum (ER): Network of interconnected membranes
  • Rough ER: Studded with ribosomes; synthesizes proteins
  • Smooth ER: Synthesizes lipids and detoxifies harmful substances
• Golgi Apparatus: Modifies, sorts, and packages proteins for transport
• Lysosomes: Digest waste materials and cellular debris

DNA Structure

• DNA is a double helix composed of nucleotide subunits
  • Nucleotides consist of a sugar, phosphate group, and one of four nitrogenous bases: adenine (A), thymine (T), cytosine (C), and guanine (G)
• The two strands of DNA are antiparallel, meaning they run in opposite directions
• Bases pair specifically: A with T, and C with G

Gene Expression

• Transcription: The process of copying DNA into messenger RNA (mRNA) in the nucleus
• Translation: The process of using mRNA to synthesize proteins at the ribosomes

Mendelian Genetics

• Laws of Inheritance: Principles governing inheritance of traits
  • Dominant and Recessive Alleles: Alleles determine traits; dominant alleles mask recessive alleles
  • Segregation: Alleles separate during gamete formation so that each gamete only receives one allele for a given trait
  • Independent Assortment: Alleles for different traits are inherited independently of each other
• Punnett Squares: Diagrams used to predict the possible genotypes and phenotypes of offspring

Theory of Evolution

• Proposed by Charles Darwin, it explains that species evolve over time through natural selection
• Natural Selection: Organisms with traits best suited to their environment are more likely to survive, reproduce, and pass on those advantageous traits

Evidence for Evolution

• Fossil record: Provides evidence of past life forms and how they have changed over time
• Comparative anatomy: Comparison of anatomical structures reveals similarities and differences between species, suggesting common ancestry
• Embryology: Study of embryonic development reveals striking similarities between various species, indicating shared evolutionary origins
• Molecular biology: Analysis of DNA and protein sequences provides strong evidence of evolutionary relationships

Speciation

• The process by which new species arise
• Often driven by factors such as
  • Geographic isolation: Physical separation of populations prevents gene flow
  • Environmental factors: Adaptations to different environments can lead to reproductive isolation and speciation

Levels of Organization in Ecology

• Organism: An individual living thing
• Population: A group of individuals of the same species living in a particular area
• Community: All the different populations of species living in a particular area
• Ecosystem: A community of organisms interacting with their physical environment
• Biome: A large-scale ecosystem with similar climate and vegetation
• Biosphere: All the living organisms and their physical environment on Earth

Biogeochemical Cycles

• The movement of matter through ecosystems
• Water Cycle: Movement of water between Earth's surface, atmosphere, and living organisms
• Carbon Cycle: Movement of carbon between the atmosphere, oceans, rocks, and living organisms
• Nitrogen Cycle: Movement of nitrogen between the atmosphere, soil, and living organisms

Ecosystem Dynamics

• Energy Flow: The movement of energy through an ecosystem
  • Food Chains/Webs: Linear pathways (food chains) or interconnected pathways (food webs) of energy transfer through consumption
• Trophic Levels: Feeding levels in a food chain or food web
  • Producers: Autotrophs that capture energy from sunlight (e.g., plants)
  • Primary Consumers: Herbivores that consume producers (e.g., rabbits)
  • Secondary Consumers: Carnivores that consume primary consumers (e.g., foxes)
  • Decomposers: Organisms that break down dead organic matter (e.g., bacteria, fungi)

Human Biology

• Body Systems: Groups of organs that work together to perform a specific function
  • Nervous System: Receives, processes, and transmits information about the environment
    • Central Nervous System (CNS): Brain and spinal cord
    • Peripheral Nervous System (PNS): Nerves that connect the CNS to the rest of the body
  • Circulatory System: Circulates blood throughout the body
    • Heart: Pumps blood
    • Blood Vessels: Arteries, veins, and capillaries
    • Blood: Contains red blood cells (transport oxygen), white blood cells (immune function), and plasma (liquid component)
  • Respiratory System: Responsible for gas exchange (oxygen and carbon dioxide)
    • Lungs: Main organs involved in gas exchange
  • Digestive System: Breaks down food into nutrients
    • Gastrointestinal Tract: Mouth, esophagus, stomach, small intestine, large intestine
  • Homeostasis: The ability to maintain a stable internal environment despite external changes

Microbiology

• Microorganisms: Tiny living organisms that can only be seen with a microscope
  • Bacteria: Prokaryotic organisms that exhibit diverse metabolic pathways
  • Viruses: Acellular entities that require a host cell to replicate
  • Fungi: Eukaryotic organisms that include yeast (single-celled) and molds (multicellular)
• Infectious diseases: Diseases caused by pathogens
  • Pathogens: Disease-causing organisms (e.g., bacteria, viruses, fungi, parasites)
  • Transmission methods: Direct contact, airborne spread, waterborne spread, and vector transmission

Plant Biology

• Photosynthesis: Process by which plants convert light energy into chemical energy (glucose) using chlorophyll
  • Equation: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂
• Plant Structure: Specialized structures for different functions
  • Roots: Absorb water and nutrients
  • Stems: Provide support and transport water and nutrients
  • Leaves: Main site for photosynthesis
• Reproductive Strategies:
  • Asexual reproduction: Production of new individuals from a single parent without the involvement of gametes (e.g., budding, fragmentation)
  • Sexual reproduction: Involves the fusion of gametes (e.g., flowers and seeds)

Animal Behavior

• Innate Behavior: Genetically programmed actions (e.g., reflexes)
• Learned Behavior: Behavior acquired through experience (e.g., conditioning)
• Social Structures: Patterns of interaction within a species
  • Communication: Methods of conveying information between individuals
  • Mating Rituals: Behaviors involved in finding and attracting mates
  • Group Dynamics: Interactions and relationships within a social group

Biotechnology

• Genetic Engineering: Techniques used to alter an organism's DNA
  • CRISPR: A powerful gene-editing tool
• Biopharmaceuticals: Use of biological processes for drug development (e.g., insulin production)
• Cloning: Production of genetically identical organisms

Test your knowledge on cell theory, types of cells, and organelles with this quiz! You'll explore key concepts such as prokaryotic and eukaryotic cells, as well as the functions of various organelles. Ideal for students studying cell biology.