p.1
Discovery of Cells by Robert Hooke
What did Robert Hooke observe in cork that resembled a honeycomb?
He saw many little compartments, which he called cells.
p.8
Cell Organelles and Their Functions
What is the primary function of lysosomes?
To digest foreign material and worn-out cell organelles.
p.5
Plasma Membrane and Selective Permeability
Why is the plasma membrane referred to as a selectively permeable membrane?
Because it allows certain substances to pass while blocking others.
p.4
Plasma Membrane and Selective Permeability
What occurs in a hypertonic solution?
The cell loses water by osmosis and may shrink.
p.3
Plasma Membrane and Selective Permeability
What is diffusion?
Diffusion is the spontaneous movement of a substance from a region of high concentration to a region of low concentration.
p.8
Cell Organelles and Their Functions
What is the relationship between the Golgi apparatus and lysosomes?
The Golgi apparatus is involved in the formation of lysosomes.
p.5
Nucleus and Genetic Material
What is the purpose of using iodine solution on onion peel during observation?
To stain the cells for better visibility under a microscope.
p.2
Discovery of Cells by Robert Hooke
Who discovered free-living cells in pond water?
Leeuwenhoek in 1674, using an improved microscope.
p.6
Cytoplasm and Cell Organelles
What do eukaryotic cells have that prokaryotic cells lack?
Nuclear membrane and membrane-bound organelles.
p.2
Microscopy Techniques in Cell Observation
What was the significance of the electron microscope discovered in 1940?
It allowed for the observation and understanding of the complex structure of the cell and its organelles.
p.11
Plasma Membrane and Selective Permeability
Why does water gather in the hollowed portion of potato cups B and C in the osmosis experiment?
Because of the concentration gradient created by the sugar and salt, causing water to move into the cups.
p.8
Cell Theory and Historical Contributions
Who was Camillo Golgi?
An Italian scientist known for his work on the nervous system and the Golgi apparatus.
p.3
Structure and Function of Cells
How are the shape and size of cells related to their function?
The shape and size of cells are related to the specific function they perform, with some cells like Amoeba having changing shapes and others like nerve cells having fixed shapes.
p.7
Cell Organelles and Their Functions
What is the function of the endoplasmic reticulum (ER)?
Transport of materials, especially proteins, and serving as a cytoplasmic framework.
p.4
Plasma Membrane and Selective Permeability
What is an isotonic solution?
A solution with the same water concentration as the cell, resulting in no net movement of water.
p.4
Plasma Membrane and Selective Permeability
What happens to dried raisins or apricots when placed in plain water?
They gain water and swell.
p.11
Structure and Function of Cells
How is a prokaryotic cell different from a eukaryotic cell?
Prokaryotic cells lack membrane-bound organelles, while eukaryotic cells have them.
p.11
Cell Division: Mitosis and Meiosis
Which type of cell division is required for growth and repair?
Mitosis; meiosis is involved in the formation of gametes.
p.9
Cell Organelles and Their Functions
What is the role of chloroplasts in plant cells?
They are important for photosynthesis.
p.3
Plasma Membrane and Selective Permeability
What is the function of the plasma membrane?
The plasma membrane separates the cell's contents from the external environment and is selectively permeable, allowing certain materials to enter or exit.
p.8
Cell Organelles and Their Functions
What can be synthesized in the Golgi apparatus?
Complex sugars from simple sugars.
p.7
Cell Organelles and Their Functions
What is membrane biogenesis?
The process of building the cell membrane using proteins and lipids.
p.2
Discovery of Cells by Robert Hooke
What did Robert Hooke discover in 1665?
He discovered cells by observing a cork slice with a primitive microscope.
p.5
Nucleus and Genetic Material
What do we observe when examining cheek cells under a microscope?
The shape of the cells can be noted and drawn.
p.2
Structure and Function of Cells
What can be observed when preparing temporary mounts of onion peels?
Similar small structures that form a larger structure like an onion bulb.
p.11
Plasma Membrane and Selective Permeability
Why does water not gather in the hollowed out portions of A and D?
In A, there is no solute to create a gradient, and in D, the boiled potato's cell structure is damaged, preventing osmosis.
p.7
Cell Organelles and Their Functions
What is the nuclear region of prokaryotic cells like?
Not well defined and not surrounded by a nuclear membrane.
p.1
Microscopy Techniques in Cell Observation
What is the purpose of the activity involving an onion bulb?
To prepare a temporary mount of onion peel for microscopic observation.
p.3
Structure and Function of Cells
What are the three main features found in almost every cell?
Plasma membrane, nucleus, and cytoplasm.
p.4
Plasma Membrane and Selective Permeability
What happens to an egg placed in a concentrated salt solution?
The egg shrinks as water passes out into the salt solution.
p.10
Cell Organelles and Their Functions
What does the Golgi apparatus do?
It stores, modifies, and packages substances manufactured in the cell.
p.4
Plasma Membrane and Selective Permeability
What is the structure of the plasma membrane made of?
Organic molecules called lipids and proteins.
p.2
Cell Organelles and Their Functions
What term did Purkinje coin in 1839?
The term 'protoplasm' for the fluid substance of the cell.
p.11
Plasma Membrane and Selective Permeability
What happens if the plasma membrane ruptures?
The cell would lose its integrity and could die due to loss of essential substances.
p.7
Cell Organelles and Their Functions
What is the general size of prokaryotic cells?
Generally small (1-10 μm).
p.6
Nucleus and Genetic Material
What do the pores in the nuclear membrane allow?
Transfer of material between the nucleus and cytoplasm.
p.7
Cell Organelles and Their Functions
What are the two types of endoplasmic reticulum?
Rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER).
p.10
Cell Wall and Plasmolysis in Plant Cells
How does the cell wall benefit plant, fungi, and bacterial cells?
It allows them to exist in hypotonic media without bursting.
p.6
Nucleus and Genetic Material
What is chromatin material?
Entangled mass of thread-like structures in a non-dividing cell.
p.9
Cell Division: Mitosis and Meiosis
What happens during mitosis?
Most cells divide for growth.
p.10
Cell Organelles and Their Functions
What are the two types of plastids found in most plant cells?
Chromoplasts and leucoplasts.
p.8
Cell Organelles and Their Functions
How do lysosomes break down complex substances?
Using powerful digestive enzymes capable of breaking down all organic material.
p.5
Cell Wall and Plasmolysis in Plant Cells
What is the composition of the plant cell wall?
Mainly composed of cellulose.
p.10
Nucleus and Genetic Material
What separates the nucleus from the cytoplasm in eukaryotic cells?
A double-layered membrane.
p.9
Cell Organelles and Their Functions
What is the primary function of mitochondria?
To generate ATP, the energy currency of the cell.
p.8
Cell Organelles and Their Functions
What are lysosomes?
Membrane-bound sacs filled with digestive enzymes that act as the cell's waste disposal system.
p.5
Plasma Membrane and Selective Permeability
What is the function of the plasma membrane?
It regulates the movement of substances like CO2 and water in and out of the cell.
p.10
Cell Wall and Plasmolysis in Plant Cells
What is located outside the cell membrane in plant cells?
A cell wall composed mainly of cellulose.
p.8
Cell Organelles and Their Functions
What role does the Golgi apparatus play in relation to the endoplasmic reticulum (ER)?
It packages and dispatches materials synthesized near the ER to various targets inside and outside the cell.
p.5
Cell Wall and Plasmolysis in Plant Cells
How do cell walls benefit plant, fungi, and bacterial cells in hypotonic media?
They allow cells to withstand very dilute external media without bursting.
p.1
Discovery of Cells by Robert Hooke
Why is Hooke's observation considered significant in the history of science?
It was the first time someone observed that living things consist of separate units.
p.3
Cell Organelles and Their Functions
What are cell organelles?
Cell organelles are specific components within a cell that perform special functions, such as making new material and clearing waste.
p.9
Cell Organelles and Their Functions
How do vacuoles contribute to plant cell structure?
They provide turgidity and rigidity.
p.4
Plasma Membrane and Selective Permeability
What happens to an egg placed in pure water after removing its shell?
The egg swells because water passes into it by osmosis.
p.10
Cell Organelles and Their Functions
What are the functions of the endoplasmic reticulum (ER)?
It serves as a passageway for intracellular transport and as a manufacturing surface.
p.5
Nucleus and Genetic Material
What happens to the coloration of cells when iodine solution is applied?
Different regions of cells get colored differently based on their chemical composition.
p.11
Cell Organelles and Their Functions
What role does the central vacuole play in mature plant cells?
It helps maintain turgidity and stores important substances including wastes.
p.11
Cell Organelles and Their Functions
What would happen to a cell without a Golgi apparatus?
It would struggle with processing and packaging proteins and lipids.
p.3
Unicellular vs Multicellular Organisms
What is the division of labor in multicellular organisms?
Different parts of the human body perform different functions, such as the heart pumping blood and the stomach digesting food.
p.9
Cell Organelles and Their Functions
What do vacuoles store in plant cells?
Solid or liquid contents, including cell sap.
p.2
Unicellular vs Multicellular Organisms
What are unicellular organisms?
Organisms made up of a single cell, such as Chlamydomonas, Paramecium, and bacteria.
p.4
Plasma Membrane and Selective Permeability
What is the role of osmosis in plant roots?
It helps in the absorption of water.
p.11
Cell Organelles and Their Functions
What are chloroplasts and their function?
Chloroplasts contain chlorophyll and perform photosynthesis.
p.2
Cell Theory and Historical Contributions
Who expanded the cell theory in 1855?
Virchow, by suggesting that all cells arise from pre-existing cells.
p.11
Unicellular vs Multicellular Organisms
How does an Amoeba obtain its food?
Through a process called phagocytosis.
p.8
Cell Theory and Historical Contributions
What significant method did Camillo Golgi develop?
The 'black reaction' for staining individual nerve and cell structures.
p.7
Cell Organelles and Their Functions
What is a key feature that distinguishes eukaryotic cells from prokaryotic cells?
Presence of membrane-bound organelles.
p.10
Plasma Membrane and Selective Permeability
What role does the cell membrane play?
It regulates the movement of materials between the cell's interior and the outer environment.
p.6
Nucleus and Genetic Material
What do chromosomes contain that is essential for inheritance?
DNA (Deoxyribo Nucleic Acid) molecules.
p.5
Cell Wall and Plasmolysis in Plant Cells
What happens to a living plant cell when it loses water through osmosis?
It undergoes shrinkage or contraction away from the cell wall, known as plasmolysis.
p.5
Cell Wall and Plasmolysis in Plant Cells
What is observed when a strong solution of sugar or salt is applied to living plant cells?
Plasmolysis occurs, indicating that only living cells can absorb water by osmosis.
p.3
Plasma Membrane and Selective Permeability
What is osmosis?
Osmosis is the movement of water molecules through a selectively permeable membrane.
p.10
Cell Division: Mitosis and Meiosis
What is the outcome of mitosis?
It divides to form two identical daughter cells with the same number of chromosomes as the mother cell.
p.2
Cell Theory and Historical Contributions
What is the cell theory?
The theory that all plants and animals are composed of cells and that the cell is the basic unit of life.
p.11
Cell Organelles and Their Functions
Which organelle is known as the powerhouse of the cell?
Mitochondria, because they produce energy (ATP).
p.9
Cell Organelles and Their Functions
What are the two types of plastids?
Chromoplasts and leucoplasts.
p.4
Plasma Membrane and Selective Permeability
What happens to a cell in a hypotonic solution?
The cell gains water by osmosis and may swell up.
p.8
Cell Organelles and Their Functions
What is the Golgi apparatus?
A system of membrane-bound vesicles arranged in stacks called cisterns, involved in storage, modification, and packaging of products.
p.7
Cell Organelles and Their Functions
What is the role of ribosomes in the cell?
Sites of protein manufacture.
p.1
Microscopy Techniques in Cell Observation
What can students do after observing the onion peel under the microscope?
Draw the structures they see on an observation sheet.
p.2
Cell Division: Mitosis and Meiosis
How do multicellular organisms originate?
They originate from a single cell that divides to produce more cells.
p.4
Plasma Membrane and Selective Permeability
What is endocytosis?
The process by which a cell engulfs food and other materials from its external environment.
p.10
Cell Division: Mitosis and Meiosis
Why do daughter cells produced by meiosis have half the number of chromosomes?
Because meiosis involves two consecutive divisions, reducing the chromosome number by half.
p.2
Unicellular vs Multicellular Organisms
Can a single cell constitute a whole organism?
Yes, as seen in organisms like Amoeba.
p.9
Cell Organelles and Their Functions
What is unique about mitochondria compared to other organelles?
They have their own DNA and ribosomes.
p.4
Plasma Membrane and Selective Permeability
What is osmosis?
The net diffusion of water across a selectively permeable membrane toward a higher solute concentration.
p.7
Cell Organelles and Their Functions
Why does rough endoplasmic reticulum (RER) appear rough under a microscope?
Because it has ribosomes attached to its surface.
p.2
Unicellular vs Multicellular Organisms
What defines multicellular organisms?
Organisms that consist of many cells grouped together, such as fungi, plants, and animals.
p.5
Nucleus and Genetic Material
What is the procedure to observe cheek cells under a microscope?
Scrape the inside surface of the cheek, transfer the material to a slide, and stain it with methylene blue.
p.11
Structure and Function of Cells
What are the characteristics of prokaryotic cells?
They have no membrane-bound organelles, chromosomes composed of nucleic acid, and very small ribosomes.
p.11
Cell Organelles and Their Functions
Where are lipids and proteins for the cell membrane synthesized?
In the endoplasmic reticulum.
p.3
Plasma Membrane and Selective Permeability
How does carbon dioxide move out of the cell?
Carbon dioxide moves out of the cell by diffusion when its concentration is higher inside the cell than outside.
p.2
Nucleus and Genetic Material
What did Robert Brown discover in 1831?
He discovered the nucleus in the cell.
p.11
Cell Division: Mitosis and Meiosis
Why do cells in organisms divide?
For growth, replacing dead cells, and forming gametes for reproduction.
p.11
Plasma Membrane and Selective Permeability
What is osmosis?
The movement of water across a selectively permeable membrane from an area of low solute concentration to high solute concentration.
p.11
Unicellular vs Multicellular Organisms
How do plant cells differ from animal cells?
Plant cells have a cell wall, chloroplasts, and a large central vacuole, while animal cells do not.
p.11
Plasma Membrane and Selective Permeability
Why is potato A necessary for the osmosis experiment?
It serves as a control to compare the effects of osmosis in the other cups.
