Podcast
Questions and Answers
Which scientist coined the term "cell"?
Which scientist coined the term "cell"?
Prokaryotic cells have a more complex structure than eukaryotic cells.
Prokaryotic cells have a more complex structure than eukaryotic cells.
False (B)
What is the name of the theory that states all living cells arise from pre-existing cells?
What is the name of the theory that states all living cells arise from pre-existing cells?
Biogenesis
The cell membrane is selectively permeable, meaning it regulates the passage of ______, waste, and secretions into and out of the cell.
The cell membrane is selectively permeable, meaning it regulates the passage of ______, waste, and secretions into and out of the cell.
Signup and view all the answers
Match the scientists with their contributions to cell theory:
Match the scientists with their contributions to cell theory:
Signup and view all the answers
Which type of cell reproduction results in four genetically different daughter cells?
Which type of cell reproduction results in four genetically different daughter cells?
Signup and view all the answers
The binomial nomenclature system was developed by Carolus Linnaeus.
The binomial nomenclature system was developed by Carolus Linnaeus.
Signup and view all the answers
What are the two main classifications used in the Five-Kingdom classification system?
What are the two main classifications used in the Five-Kingdom classification system?
Signup and view all the answers
Bacillus anthracis is an example of a __________ microorganism.
Bacillus anthracis is an example of a __________ microorganism.
Signup and view all the answers
Match the following taxonomic ranks with their respective examples:
Match the following taxonomic ranks with their respective examples:
Signup and view all the answers
Which of the following types of cell walls do archaeans possess?
Which of the following types of cell walls do archaeans possess?
Signup and view all the answers
The glycocalyx only forms a capsule that is loosely attached to the cell wall.
The glycocalyx only forms a capsule that is loosely attached to the cell wall.
Signup and view all the answers
What type of DNA is found in the nucleoid of prokaryotic cells?
What type of DNA is found in the nucleoid of prokaryotic cells?
Signup and view all the answers
Pili are hair-like structures observed in G(-) bacteria and are NOT associated with ______.
Pili are hair-like structures observed in G(-) bacteria and are NOT associated with ______.
Signup and view all the answers
Match the bacteria to their corresponding characteristics:
Match the bacteria to their corresponding characteristics:
Signup and view all the answers
What type of arrangement do flagella have when they are located all over the surface of a bacterium?
What type of arrangement do flagella have when they are located all over the surface of a bacterium?
Signup and view all the answers
Endospores are highly susceptible to heat and cold.
Endospores are highly susceptible to heat and cold.
Signup and view all the answers
What is the arrangement of two flagella like fibrils in spirochetes called?
What is the arrangement of two flagella like fibrils in spirochetes called?
Signup and view all the answers
Which component is responsible for protein synthesis?
Which component is responsible for protein synthesis?
Signup and view all the answers
The cytoskeleton is primarily responsible for energy production within the cell.
The cytoskeleton is primarily responsible for energy production within the cell.
Signup and view all the answers
What structure controls all cell functions?
What structure controls all cell functions?
Signup and view all the answers
The membrane-bound organelle known for packaging proteins is the __________.
The membrane-bound organelle known for packaging proteins is the __________.
Signup and view all the answers
Match the following structures with their functions:
Match the following structures with their functions:
Signup and view all the answers
What type of membrane does a Gram-negative cell wall possess?
What type of membrane does a Gram-negative cell wall possess?
Signup and view all the answers
Cilia are longer than flagella and have a whip-like movement.
Cilia are longer than flagella and have a whip-like movement.
Signup and view all the answers
What type of material do lysosomes break down?
What type of material do lysosomes break down?
Signup and view all the answers
The gelatinous matrix inside the nucleus is called __________.
The gelatinous matrix inside the nucleus is called __________.
Signup and view all the answers
Which of these organelles is prominent in mammalian liver cells?
Which of these organelles is prominent in mammalian liver cells?
Signup and view all the answers
Study Notes
Cell Structure and Taxonomy
- Cells are the fundamental units of all organisms.
- Cells exhibit basic characteristics of life, including metabolism (all chemical reactions in a cell), growth and reproduction, response to stimuli (light, heat, cold, and chemicals), and mutations.
- Robert Hooke invented the compound microscope and coined the term "cell."
- Matthias Schleiden (botanist) proposed plant cell theory.
- Theodor Schwann (zoologist) proposed animal cell theory.
- Rudolf Virchow proposed biogenesis (the idea that cells come from other cells).
- Eukaryotes have a true nucleus and complex membrane-bound organelles; examples include algae, protozoa, fungi, plants, animals, and humans.
- Prokaryotes lack membrane-bound organelles and a true nucleus.
- Bacteria and archaea are examples.
- Prokaryotes are 10x smaller than eukaryotes.
Eukaryotic Cell Structure
- Cell membrane (AKA plasma or cytoplasmic membrane) regulates the passage of nutrients, waste, and secretions into and out of the cell.
- The cell membrane is a mosaic of proteins and phospholipids.
- Nucleus: controls all cellular functions.
- Parts include chromosomes (DNA and histones), nucleoplasm (gelatinous matrix), nuclear membrane, nuclear pores, nucleolus (rRNA production).
- Cytoplasm is a semi-fluid, gelatinous, nutrient matrix containing organelles.
- Cytosol is cytoplasm without the organelles or storage granules.
- The endoplasmic reticulum is a highly convoluted system of interconnected membranes (rough and smooth).
- Rough ER has ribosomes for protein synthesis (40, 60, and 80S - Svedberg units).
- Ribosomes synthesize proteins.
- Golgi complex packages proteins into membrane-enclosed vesicles for storage or export.
- Lysosomes contain lysozyme and break down foreign material; autolysis is the process where the cell breaks down internal components.
- Peroxisomes degrade hydrogen peroxide and contain catalase (2H₂O₂ → 2H₂O + O₂).
- Mitochondria produce adenosine triphosphate (ATP).
- Plastids are energy-producing organelles in plants and algae; chloroplasts are involved in photosynthesis (CO₂ + H₂O → CHO + O₂).
- The cytoskeleton is a system of fibers throughout the cytoplasm that provide structure, cell division, contraction, motility, and chromosome movement.
Prokaryotic Cell Structure
- Cell membrane, cell wall, and glycocalyx form the prokaryotic cell envelope.
- The cell wall is thinner in gram-negative bacteria compared to gram-positive bacteria.
- Gram-positive cell walls have thick peptidoglycan and lipo/teichoic acid molecules.
- Gram-negative cell walls have thinner peptidoglycan and lipid outer membrane.
- Mycoplasma species lack a cell wall.
- Archaeans have peptidoglycan-less cell walls.
- Glycocalyx (capsule or slime layer) can be firmly or loosely attached to the cell wall; the capsule is anti-phagocytic.
- Pili or fimbriae are hair-like structures aiding in attachment and transfer of genetic material (conjugation).
- Prokaryotic cells contain a nucleoid (DNA-occupied area in the cytoplasm), plasmids (extrachromosomal circular DNA), cytoplasm containing enzymes, and dissolved oxygen, waste products, and essential nutrients. Cytoplasmic particles include ribosomes (30, 50, and 70S).
- Flagella are protein structures for movement (peritrichous, lophotrichous, amphitrichous, and monotrichous).
- Axial filaments are found in spirochete bacteria.
- Endospores (spores) are resistant to heat, cold, drying, and chemicals; found in Bacillus and Clostridium.
Taxonomy
- Taxonomy is the classification, nomenclature, and identification of organisms.
- Organisms are categorized into taxa (e.g., groups) based on similarities.
- Binomial nomenclature (e.g., Escherichia coli) is a standardized naming system.
- Classification schemes include five-kingdom and three-domain systems.
Cell Reproduction
- Mitosis is somatic cell division; resulting in two identical daughter cells
- Meiosis is gamete (sex cell) division. Results in four genetically distinct daughter cells.
- Binary fission is prokaryotic cell reproduction; resulting in two identical daughter cells. A circular chromosome replicates and the cell divides.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the fundamental aspects of cell structure and taxonomy. Learn about the differences between eukaryotic and prokaryotic cells, cell theory contributions by renowned scientists, and the characteristics that define life at the cellular level. Test your knowledge on cellular organization and the discovery of cells.
