Podcast
Questions and Answers
What characteristic is true about prokaryotic cells compared to eukaryotic cells?
What characteristic is true about prokaryotic cells compared to eukaryotic cells?
- Prokaryotic cells are larger than eukaryotic cells.
- Prokaryotic cells lack well-defined organelles. (correct)
- Prokaryotic cells have a membrane-bound nucleus.
- Prokaryotic cells contain multiple complex organelles.
Which statement about the structure of prokaryotic cells is accurate?
Which statement about the structure of prokaryotic cells is accurate?
- Prokaryotic cells contain a nuclear envelope.
- Prokaryotic cells have an internal compartmentalization similar to all eukaryotes.
- Prokaryotic cells possess a plasma membrane encasing their components. (correct)
- Prokaryotic cells have complex membrane-bound organelles.
Which regions are part of the architectural structure of a prokaryotic cell?
Which regions are part of the architectural structure of a prokaryotic cell?
- Endoplasmic reticulum, Golgi apparatus, ribosomes.
- Nucleus, cytoplasmic region, cell wall.
- Flagella, outer covering, cytoplasmic region. (correct)
- Cytoplasm, nuclear envelope, mitochondria.
What is NOT a characteristic of prokaryotic cells?
What is NOT a characteristic of prokaryotic cells?
What do prokaryotic cells use for enzyme attachment since they lack a separate respiratory enzyme system?
What do prokaryotic cells use for enzyme attachment since they lack a separate respiratory enzyme system?
What is the primary component of the cell wall that provides mechanical strength?
What is the primary component of the cell wall that provides mechanical strength?
What substance acts as the cementing layer between the primary walls of adjacent cells?
What substance acts as the cementing layer between the primary walls of adjacent cells?
Which layer of the cell wall is laid down by cells that are actively growing?
Which layer of the cell wall is laid down by cells that are actively growing?
What role does the plasma membrane primarily serve?
What role does the plasma membrane primarily serve?
Which cell shape is characterized by elongated structures?
Which cell shape is characterized by elongated structures?
What primarily determines the total mass of an organ or organism?
What primarily determines the total mass of an organ or organism?
Which function does the cell wall NOT provide?
Which function does the cell wall NOT provide?
Which statement regarding cell number in multicellular organisms is true?
Which statement regarding cell number in multicellular organisms is true?
What is a characteristic feature of secondary cell walls?
What is a characteristic feature of secondary cell walls?
What is the outermost structure found in most plant cells?
What is the outermost structure found in most plant cells?
What is found in the gel-like matrix of the cell wall?
What is found in the gel-like matrix of the cell wall?
Which component is NOT typically found in plant cell walls?
Which component is NOT typically found in plant cell walls?
Eukaryotic cells share which of the following characteristics?
Eukaryotic cells share which of the following characteristics?
Which type of cell is most likely to have a spherical shape?
Which type of cell is most likely to have a spherical shape?
What best explains why the cells of an elephant are not necessarily larger than those of an ant?
What best explains why the cells of an elephant are not necessarily larger than those of an ant?
Which component is not typically found in eukaryotic cells?
Which component is not typically found in eukaryotic cells?
What is the primary composition of the prokaryotic cell wall?
What is the primary composition of the prokaryotic cell wall?
Which of the following structures are found in eukaryotic cells but not in prokaryotic cells?
Which of the following structures are found in eukaryotic cells but not in prokaryotic cells?
What role do plasmids serve in prokaryotic cells?
What role do plasmids serve in prokaryotic cells?
What is a key characteristic that distinguishes eukaryotic cells from prokaryotic cells?
What is a key characteristic that distinguishes eukaryotic cells from prokaryotic cells?
What function does the cell envelope serve in prokaryotic cells?
What function does the cell envelope serve in prokaryotic cells?
In which types of organisms can eukaryotic cells be found?
In which types of organisms can eukaryotic cells be found?
How do flagella benefit prokaryotic cells?
How do flagella benefit prokaryotic cells?
What is the primary function of the eukaryotic cell nucleus?
What is the primary function of the eukaryotic cell nucleus?
Which of the following structures is classified as a double membrane-bound organelle?
Which of the following structures is classified as a double membrane-bound organelle?
What is the primary function of the nucleus within a eukaryotic cell?
What is the primary function of the nucleus within a eukaryotic cell?
Which of the following is categorized as a non-membrane-bound organelle?
Which of the following is categorized as a non-membrane-bound organelle?
Which of the following statements about cytoplasm is accurate?
Which of the following statements about cytoplasm is accurate?
What role do nuclear pores play in the function of the nucleus?
What role do nuclear pores play in the function of the nucleus?
Which organelle is responsible for controlling metabolic activity within a cell?
Which organelle is responsible for controlling metabolic activity within a cell?
Which of the following organelles is present only in eukaryotic cells?
Which of the following organelles is present only in eukaryotic cells?
What is primarily contained within the nucleus of a eukaryotic cell?
What is primarily contained within the nucleus of a eukaryotic cell?
What is the primary role of the plasma membrane in a cell?
What is the primary role of the plasma membrane in a cell?
Which of the following correctly describes the composition of the plasma membrane?
Which of the following correctly describes the composition of the plasma membrane?
How does the plasma membrane contribute to cellular signaling?
How does the plasma membrane contribute to cellular signaling?
What structure enables the plasma membrane to remain flexible?
What structure enables the plasma membrane to remain flexible?
Which of the following statements about the permeability of the plasma membrane is true?
Which of the following statements about the permeability of the plasma membrane is true?
Which process is NOT facilitated by the plasma membrane?
Which process is NOT facilitated by the plasma membrane?
What is the thickness of the plasma membrane usually measured to be?
What is the thickness of the plasma membrane usually measured to be?
Who first proposed the fluid mosaic model of the plasma membrane?
Who first proposed the fluid mosaic model of the plasma membrane?
Flashcards
What is a cell?
What is a cell?
A unit of biological activity enclosed by a selectively permeable membrane, capable of independent reproduction.
What is the difference between prokaryotic and eukaryotic cells?
What is the difference between prokaryotic and eukaryotic cells?
Prokaryotic cells lack a nucleus and most other membrane-bound organelles found in eukaryotes.
What are the two types of prokaryotes?
What are the two types of prokaryotes?
Prokaryotes are classified into two domains: Bacteria and Archaea.
Describe the structure of a prokaryotic cell.
Describe the structure of a prokaryotic cell.
Signup and view all the flashcards
What are some key features of prokaryotic cells?
What are some key features of prokaryotic cells?
Signup and view all the flashcards
Cell Wall
Cell Wall
Signup and view all the flashcards
Plasma Membrane
Plasma Membrane
Signup and view all the flashcards
Cytoplasmic Region
Cytoplasmic Region
Signup and view all the flashcards
Plasmids
Plasmids
Signup and view all the flashcards
Flagella
Flagella
Signup and view all the flashcards
Eukaryotic Cell
Eukaryotic Cell
Signup and view all the flashcards
Nucleus
Nucleus
Signup and view all the flashcards
Membrane-bound Compartments
Membrane-bound Compartments
Signup and view all the flashcards
Cytoplasm
Cytoplasm
Signup and view all the flashcards
Prokaryotic Cells
Prokaryotic Cells
Signup and view all the flashcards
Plant Cells
Plant Cells
Signup and view all the flashcards
Animal Cells
Animal Cells
Signup and view all the flashcards
What is the cell wall?
What is the cell wall?
Signup and view all the flashcards
What is the plasma membrane?
What is the plasma membrane?
Signup and view all the flashcards
What is the middle lamella?
What is the middle lamella?
Signup and view all the flashcards
What is the primary cell wall?
What is the primary cell wall?
Signup and view all the flashcards
What is the secondary cell wall?
What is the secondary cell wall?
Signup and view all the flashcards
What is the microfibrillar network?
What is the microfibrillar network?
Signup and view all the flashcards
What is the intracellular fluid?
What is the intracellular fluid?
Signup and view all the flashcards
What is the extracellular fluid?
What is the extracellular fluid?
Signup and view all the flashcards
Endocytosis
Endocytosis
Signup and view all the flashcards
Exocytosis
Exocytosis
Signup and view all the flashcards
Cell Organelles
Cell Organelles
Signup and view all the flashcards
Non-membrane Bound Organelles
Non-membrane Bound Organelles
Signup and view all the flashcards
Ribosomes
Ribosomes
Signup and view all the flashcards
Membrane-bound Organelles
Membrane-bound Organelles
Signup and view all the flashcards
What is cytoplasm?
What is cytoplasm?
Signup and view all the flashcards
What is the nucleus?
What is the nucleus?
Signup and view all the flashcards
What are non-membrane-bound organelles?
What are non-membrane-bound organelles?
Signup and view all the flashcards
What are single-membrane-bound organelles?
What are single-membrane-bound organelles?
Signup and view all the flashcards
What are double-membrane-bound organelles?
What are double-membrane-bound organelles?
Signup and view all the flashcards
What are chromosomes?
What are chromosomes?
Signup and view all the flashcards
What is the nucleolus?
What is the nucleolus?
Signup and view all the flashcards
What is the nuclear membrane?
What is the nuclear membrane?
Signup and view all the flashcards
Study Notes
Cell Theory
- Robert Hooke (1665) coined the term "cell" observing cork under a microscope, describing it as hollow compartments.
- Anton van Leeuwenhoek (1675) improved microscopes and observed free-living cells.
- Matthias Schleiden (1838-1839) stated cells were the fundamental units in plants.
- Theodor Schwann (1838-1839) extended this to animals.
- Rudolf Virchow (1858) concluded that cells arise from pre-existing cells, a critical addition to the cell theory.
- Louis Pasteur (1865) provided experimental support for Virchow's ideas.
Modern Cell Theory
- All living organisms are composed of one or more cells and cell products.
- All metabolic reactions occur within cells.
- Cells originate only from pre-existing cells.
- The cell is the fundamental unit of life.
Definitions of Cell
- A.G. Lowe and P. Siekevitz (1963): A unit of biological activity bounded by a semipermeable membrane, capable of self-reproduction in a medium free of other living systems.
- Wilson and Morrison (1966): An integrated and continuously changing system.
- John Paul (1970): The simplest integrated organization in living systems, capable of independent survival.
Prokaryotic Cells
- Simplest and smaller than eukaryotic cells.
- Lack a nucleus and most other organelles.
- Two types: Bacteria and Archaea.
- Possibly the first life forms (3.5 billion years ago).
- Three architectural regions: Flagella, Outer covering, Cytoplasmic region
- Prokaryotic cells consist of DNA, RNA, proteins (in the cytoplasm), surrounded by cell membrane
- Lack membrane-bound organelles like ER, Golgi apparatus, mitochondria, centrioles, etc.
- Lack of nuclear envelope and any other cytoplasmic membrane.
- Do not contain nucleoli, cytoskeleton (microfilaments and microtubules), centrioles, etc.
Prokaryotic cell structure
- Cytoplasm: Jelly-like substance containing DNA, ribosomes, and inclusions.
- Nucleoid (DNA): Region containing the cell's genetic material.
- Ribosomes: Sites of protein synthesis.
- Cell wall: Rigid outer layer (primarily peptidoglycan in bacteria, different in Archaea).
- Plasma membrane: Regulates what enters and exits the cell
- Capsule: Gelatinous layer outside the cell wall, protective.
- Flagella/Pili: Appendages for movement.
- Plasmid: Extrachromosomal DNA.
Prokaryotic cells – Additional points
- The cell wall acts as a barrier, prevents expansion and bursting in hypotonic environments, protects against exterior forces.
- Flagella help in movement by rotating, a propeller-like motion.
- Pili/fimbriae aid in attachment, or communication between bacteria
- The cytoplasmic region contains many inclusions.
- Plasmids are extrachromosomal DNA and enable additional functions like antibiotic resistance.
Eukaryotic Cells
- Larger than prokaryotic cells.
- Contain a nucleus and membrane-bound organelles.
- Includes organisms like plants, animals, fungi, and protists.
- Contain membrane-bound organelles to perform specific metabolic activities, compartmentalizing functions within the cell.
- The major difference between prokaryotes and eukaryotes is that eukaryotic cells contain membrane-bound compartments in which specific metabolic activities take place
Eukaryotic Cell Shapes
- Spherical (eggs of many animals)
- Cuboidal (thyroid gland follicles)
- Elongated (neurons)
- Flattened (squamous epithelium)
- Spindle (smooth muscle fibres)
- Branched (pigment cells of skin)
Cell Size
- Prokaryotic cells: 1 µm – 10 µm (micrometers)
- Eukaryotic cells: 10 µm – 100 µm
Cell Number
- Number of cells varies greatly: Unicellular organisms (one cell), multicellular organisms (many cells)
- Number of cells is indefinite in most multicellular organisms but fixed in some organisms.
Cell Components
- Cell Wall (plants, algae) - rigid outer layer, made of cellulose, pectin, hemicellulose and lignin.
- Plasma membrane (all cells): thin layer regulating passage between interior and external environment, semipermeable, is a lipid bilayer, is a barrier and controls transport.
Function of Cell Wall
- Protection, support, and maintaining cell shape
- Preventing bursting in hypotonic environments
- Act as a mechanical barrier
- Providing a framework for growth
- Providing a surface for certain interactions
- A site for storage of regulatory molecules (detecting pathogens, controlling responses)
Cell Organelles
- Prokaryotic cells: Ribosomes, cytoskeletons
- Eukaryotic cells: Vacuole, Lysosome, Golgi apparatus, ER, Nucleus, mitochondria, chloroplasts and other membrane bound organelles
- Organelles without membrane: Cell wall, ribosomes, cytoskeleton
- Single membrane-bound organelles: vacuole, lysosome, Golgi apparatus, ER
- Double membrane-bound organelles: nucleus, mitochondria, chloroplast
Plasma Membrane
- Barrier between cell exterior and interior
- Selectively permeable, regulating what enters and leaves the cell.
- Controls the movement of materials both in and out of the cell.
- Is a lipid bi-layer
Plasma membrane structure
- Primarily composed of phospholipids, proteins, carbohydrates and often cholesterol
- The presence of certain specialized components, is also described as the fluid mosaic model.
- Has a structure that described in detail the arrangements of components in the eukaryotic cell.
Other Cell Structures
-
Vacuoles: Storage compartments for nutrients or waste products (eukaryotes - especially plant cells have large vacuoles).
-
Centrosomes/Centrioles: Organizing centers for microtubules during cell division.
-
Mitochondria: Powerhouses of the cell, producing ATP (energy).
-
Cilia and Flagella: Movement structures.
-
Ribosomes: Protein synthesis sites (present in both prokaryotes and eukaryotes).
-
Cytoskeleton: Network of filaments maintaining cell shape and support, important in motility and cell division (found in all eukaryotic cells)
-
Microbodies: Membrane-bound organelles containing various enzymes (e.g., peroxisomes)
-
Golgi Apparatus: Modifies, sorts, and packages proteins and lipids.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge about prokaryotic cells and their unique characteristics compared to eukaryotic cells. This quiz covers various aspects such as structure, function, and important components of prokaryotic cells. It's designed for students studying cell biology and foundational concepts in life sciences.
