Cell Structure and Function Introduction

A cell

Robert Hooke

Antony Van Leeuwenhoek

<p>Protoplasm</p> Signup and view all the answers

<p>Robert Brown</p> Signup and view all the answers

<p>Omnis cellula e cellula</p> Signup and view all the answers

<p>A single cell divides and redivides, then differentiates into different types, forming tissues, which then form organs, and eventually, the individual takes shape.</p> Signup and view all the answers

<p>He observed dead cells that resembled honeycomb-like structures in cork.</p> Signup and view all the answers

<p>He was the first to observe living cells in pond water.</p> Signup and view all the answers

<p>The discovery of the nucleus helped in understanding the cell's internal structure and function.</p> Signup and view all the answers

<p>Protoplasm.</p> Signup and view all the answers

<p>He established that all cells arise from pre-existing cells.</p> Signup and view all the answers

<p>Hooke's observation led to the discovery of cells and paved the way for further research in cell biology.</p> Signup and view all the answers

<p>The discovery of the nucleus by Robert Brown revealed the presence of a control center in cells, which is responsible for regulating cellular activities.</p> Signup and view all the answers

<p>The concept highlights the continuity of life and underscores the idea that cells give rise to cells, forming a continuous chain of life.</p> Signup and view all the answers

<p>Cells differentiate and specialize to form tissues, which in turn form organs, ultimately giving rise to a fully formed organism.</p> Signup and view all the answers

<p>Purkinje introduced the term 'protoplasm' to describe the living matter inside cells, highlighting the dynamic and living nature of cellular content.</p> Signup and view all the answers

<p>Van Leeuwenhoek's observation marked the first time living cells were observed, revealing the diversity of cellular life.</p> Signup and view all the answers

<p>M. Schleiden and T. Schwann</p> Signup and view all the answers

<p>The cell is the basic structural and functional unit of life; all organisms are composed of cells.</p> Signup and view all the answers

<p>Observing onion peel cells under a compound microscope</p> Signup and view all the answers

<p>Made it possible to observe and understand the complex structure of cells and their organelles</p> Signup and view all the answers

<p>Regularly arranged linear or rectangular compartments</p> Signup and view all the answers

<p>Pushed towards the periphery</p> Signup and view all the answers

<p>Rudolf Virchow</p> Signup and view all the answers

<p>All organisms are composed of cells</p> Signup and view all the answers

<p>To visualize the cells under a microscope</p> Signup and view all the answers

<p>To study the structure and function of cells</p> Signup and view all the answers

<p>The cell theory is significant because it states that all living organisms are composed of cells, which are the basic structural and functional units of life, and that all cells arise from pre-existing cells.</p> Signup and view all the answers

<p>The purpose of using a compound microscope to observe onion peel cells is to examine the structure of the cells, including the cell walls and nucleus, in detail.</p> Signup and view all the answers

<p>The discovery of the electron microscope made it possible to observe and understand the complex structure of cells and their organelles at the ultrastructural level.</p> Signup and view all the answers

<p>The central vacuole pushes the nucleus towards the periphery of the cell.</p> Signup and view all the answers

<p>Safranin is used to stain onion peel cells to make their structures more visible under the microscope.</p> Signup and view all the answers

<p>The regular arrangement of epidermal cells of onion peel suggests that they are organized in a specific pattern to form the epidermal tissue.</p> Signup and view all the answers

<p>M. Schleiden and T. Schwann formulated the cell theory, which states that cells are the basic structural and functional units of life, and that all cells arise from pre-existing cells.</p> Signup and view all the answers

<p>Glycerine is used to mount onion peel cells on a microscope slide to preserve the cells and prevent them from drying out.</p> Signup and view all the answers

<p>The cell theory provided a fundamental understanding of the development and organization of living organisms, and revealed that cells are the basic units of life.</p> Signup and view all the answers

<p>The observation that the nucleus is pushed towards the periphery of the epidermal cells of onion peel suggests that the central vacuole is large and occupies a significant portion of the cell volume.</p> Signup and view all the answers

<p>The cell theory is significant in understanding the structure and function of living organisms as it provides a fundamental understanding of the basic unit of life. The discovery of the electron microscope further expanded our understanding of cellular structure and function by enabling us to observe and study the complex structure of cells and their organelles.</p> Signup and view all the answers

<p>The regular, linear or rectangular arrangement of epidermal cells of onion peel reflects the cell theory, which states that cells are the basic structural and functional units of life. This arrangement reveals that these cells are composed of rigid cell walls and have a central vacuole that pushes the nucleus towards the periphery.</p> Signup and view all the answers

<p>Staining onion peel cells with safranin is significant because it enhances the visibility of the cell structures, allowing for better observation under a microscope. This facilitates the study of the morphology and arrangement of cells, which is essential for understanding cellular structure and function.</p> Signup and view all the answers

<p>The central vacuole in epidermal cells of onion peel pushes the nucleus towards the periphery, revealing the dynamic organization of cellular structures. This arrangement highlights the importance of cellular compartments in maintaining cellular function and structure.</p> Signup and view all the answers

<p>The discovery of the electron microscope enabled the observation of complex cellular structures and organelles, expanding our understanding of cellular structure and function. This discovery further supports the cell theory, which states that cells are the basic structural and functional units of life.</p> Signup and view all the answers

<p>The observation of onion peel cells under a microscope demonstrates the principles of the cell theory by showing that cells are the basic structural and functional units of life. This observation reveals the organization of cells, their composition, and their functional structures, such as the central vacuole and nucleus.</p> Signup and view all the answers

<p>The cell theory is significant in understanding the development and organization of living organisms because it provides a foundation for understanding cellular differentiation and the organization of tissues and organs. The cell theory highlights the importance of cells in development and organization, and how they differentiate to form specialized structures and functions.</p> Signup and view all the answers

<p>The process of observing plant cells demonstrates the principles of scientific inquiry by involving systematic observation, experimentation, and data analysis. This process reveals the importance of careful observation, experimentation, and critical thinking in scientific investigation, as well as the need for controlled conditions and precise techniques.</p> Signup and view all the answers

<p>The contributions of M. Schleiden and T. Schwann were significant in establishing the cell theory, which laid the foundation for modern cellular biology. Their work recognized the importance of cells as the basic structural and functional units of life, and paved the way for further research into cellular structure and function.</p> Signup and view all the answers

<p>The structure of epidermal cells of onion peel reflects the principles of cellular organization by demonstrating the arrangement of cellular components, such as the cell wall, central vacuole, and nucleus. This structure reveals the complex relationships between cellular components, highlighting the importance of cellular compartments and their interactions in maintaining cellular function.</p> Signup and view all the answers

<p>To obtain squamous epithelial cells.</p> Signup and view all the answers

<p>Methylene blue.</p> Signup and view all the answers

<p>Flat and polygonal.</p> Signup and view all the answers

<p>To mount the stained material on a microscope slide.</p> Signup and view all the answers

<p>To avoid injuring the buccal mucosa.</p> Signup and view all the answers

<p>It confirms that the basic structural unit of life is the cell.</p> Signup and view all the answers

<p>To ensure even staining and clear observation of the cells.</p> Signup and view all the answers

<p>To spread the cells evenly and remove air bubbles.</p> Signup and view all the answers

<p>To collect squamous epithelial cells from the cheek for microscopic observation.</p> Signup and view all the answers

<p>To stain the squamous epithelial cells.</p> Signup and view all the answers

<p>To prevent excessive staining and ensure clear visibility of the cells under the microscope.</p> Signup and view all the answers

<p>To mount the stained material on a microscope slide.</p> Signup and view all the answers

<p>To observe the cells at different magnifications and obtain a detailed understanding of their structure.</p> Signup and view all the answers

<p>Flat and polygonal.</p> Signup and view all the answers

<p>To ensure that the cells are evenly distributed and can be observed clearly.</p> Signup and view all the answers

<p>It confirms that the basic structural unit of life is the cell.</p> Signup and view all the answers

<p>20 um to 30 um</p> Signup and view all the answers

<p>Ostrich egg</p> Signup and view all the answers

<p>Elongated and branched</p> Signup and view all the answers

<p>0.01 mm</p> Signup and view all the answers

<p>Discoidal or saucer-shaped</p> Signup and view all the answers

<p>7.5 um</p> Signup and view all the answers

<p>20 um to 30 um</p> Signup and view all the answers

<p>Elongated and branched</p> Signup and view all the answers

<p>Ostrich egg</p> Signup and view all the answers

<p>Red blood cell</p> Signup and view all the answers

<p>To perform a specific function</p> Signup and view all the answers

<p>Micrometers or microns (μm)</p> Signup and view all the answers

<p>The shape of cells is often related to the different functions they perform.</p> Signup and view all the answers

<p>Human white blood cells are amoeboid, which allows them to squeeze out through capillary walls.</p> Signup and view all the answers

<p>Red blood cells are circular and biconcave, which allows them to move easily through small spaces and transport oxygen.</p> Signup and view all the answers

<p>Nerve cells are long, which allows them to conduct impulses from distant parts of the body to the brain and vice-versa.</p> Signup and view all the answers

<p>Muscle cells are long and contractile, which helps in the movement of bones.</p> Signup and view all the answers

<p>Xylem vessels are long and elongated, which helps in the conduction of water and minerals.</p> Signup and view all the answers

<p>The size of an organism is dependent upon the number of cells, not on the size of the cell.</p> Signup and view all the answers

<p>Guard cells are kidney-shaped, which allows them to open and close stomata to allow exchange of gases.</p> Signup and view all the answers

<p>Amoeboid; their amoeba-like movement with pseudopodia enables them to squeeze out through capillary walls.</p> Signup and view all the answers

<p>Circular and biconcave; this shape allows them to move easily through small spaces and transport oxygen.</p> Signup and view all the answers

<p>Long; this shape enables them to conduct impulses from distant parts of the body to the brain and vice-versa.</p> Signup and view all the answers

<p>Long and contractile; this shape enables them to help in the movement of bones.</p> Signup and view all the answers

<p>Long and elongated; this shape enables them to conduct water and minerals.</p> Signup and view all the answers

<p>Kidney-shaped; this shape enables them to open and close stomata to allow exchange of gases.</p> Signup and view all the answers

<p>Unicellular organisms consist of a single cell that performs all life processes, whereas multicellular organisms consist of multiple cells.</p> Signup and view all the answers

<p>The size of an organism is dependent upon the number of cells, not the size of the cell.</p> Signup and view all the answers

<p>Multicellular organisms</p> Signup and view all the answers

<p>Division of labour</p> Signup and view all the answers

<p>Cell</p> Signup and view all the answers

<p>Cell membrane, cytoplasm, and nucleus</p> Signup and view all the answers

<p>To perform different functions in the body</p> Signup and view all the answers

<p>A small box-like structure</p> Signup and view all the answers

<p>Cells are the basic structural and functional units of life</p> Signup and view all the answers

<p>Specialization of cells to perform different functions due to division of labor.</p> Signup and view all the answers

<p>Box-like structures</p> Signup and view all the answers

<p>Cell membrane, Cytoplasm, and Nucleus</p> Signup and view all the answers

<p>It allows different cells to perform different functions of the body.</p> Signup and view all the answers

<p>The cell</p> Signup and view all the answers

<p>They perform different functions due to specialization.</p> Signup and view all the answers

<p>Because cells are the basic structural and functional units of life.</p> Signup and view all the answers

<p>Protoplasm</p> Signup and view all the answers

<p>It protects the internal components of the cell, provides shape to the cell, and allows materials to enter and leave the cell.</p> Signup and view all the answers

<p>An outer, non-living, and freely permeable layer found in plant cells.</p> Signup and view all the answers

<p>Nucleoplasm is the protoplasm found in the nucleus, while cytoplasm is the protoplasm found outside the nucleus.</p> Signup and view all the answers

<p>It allows certain molecules to pass through while regulating the passage of others.</p> Signup and view all the answers

<p>It is made up of organic molecules called lipids and proteins.</p> Signup and view all the answers

<p>The cell membrane is a living, semi-permeable layer, while the cell wall is a non-living, freely permeable layer.</p> Signup and view all the answers

<p>It protects the internal components of the cell from the outside environment.</p> Signup and view all the answers

<p>It helps maintain the cell's shape and structure.</p> Signup and view all the answers

<p>It allows nutrients and essential elements to enter the cell, while waste materials leave the cell.</p> Signup and view all the answers

<p>Cell organelle</p> Signup and view all the answers

<p>Cell wall</p> Signup and view all the answers

<p>Protects the cell, provides shape, and regulates the movement of materials in and out of the cell</p> Signup and view all the answers

<p>Nucleoplasm</p> Signup and view all the answers

<p>Protoplasm</p> Signup and view all the answers

<p>Performs specific functions, provides shape, and supports the cell's metabolic activities</p> Signup and view all the answers

<p>Allows nutrients to enter and waste materials to leave the cell</p> Signup and view all the answers

<p>Organic molecules called lipids and proteins</p> Signup and view all the answers

<p>Provides additional protection and support to the plant cell</p> Signup and view all the answers

<p>Nucleoplasm is found in the nucleus, while cytoplasm is found outside the nucleus</p> Signup and view all the answers

<p>Perform specific functions necessary for the cell's survival</p> Signup and view all the answers

<p>Cell wall</p> Signup and view all the answers

<p>Cell membrane</p> Signup and view all the answers

<p>Matrix, organelles, and non-living inclusions like vacuoles and granules</p> Signup and view all the answers

<p>Nucleus</p> Signup and view all the answers

<p>Nucleoplasm</p> Signup and view all the answers

<p>Nucleolus</p> Signup and view all the answers

<p>Chromatin threads</p> Signup and view all the answers

<p>It controls the passage of materials between cytoplasm and nucleoplasm</p> Signup and view all the answers

<p>Non-living and freely permeable</p> Signup and view all the answers

<p>Living and selectively permeable</p> Signup and view all the answers

<p>bacterial and plant cells</p> Signup and view all the answers

<p>to control the passage of materials</p> Signup and view all the answers

<p>cytoplasm</p> Signup and view all the answers

<p>nucleus</p> Signup and view all the answers

<p>nuclear membrane, nucleoplasm, nucleolus, and chromatin material</p> Signup and view all the answers

<p>to control the passage of materials between cytoplasm and nucleoplasm</p> Signup and view all the answers

<p>nucleoplasm</p> Signup and view all the answers

<p>to produce ribosomes</p> Signup and view all the answers

<p>chromatin reticulum</p> Signup and view all the answers

<p>the cell wall is non-living and freely permeable, while the cell membrane is living and selectively permeable</p> Signup and view all the answers

<p>Cell wall</p> Signup and view all the answers

<p>Cytoplasm</p> Signup and view all the answers

<p>Nucleus</p> Signup and view all the answers

<p>Nucleoplasm</p> Signup and view all the answers

<p>It surrounds the nucleus and separates it from the cytoplasm, controlling the passage of materials.</p> Signup and view all the answers

<p>Chromatin reticulum</p> Signup and view all the answers

<p>Cell membrane</p> Signup and view all the answers

<p>Nucleolus</p> Signup and view all the answers

<p>To control the passage of materials between the cytoplasm and nucleoplasm.</p> Signup and view all the answers

<p>Cytoplasm</p> Signup and view all the answers

<p>To provide a thick, protective layer</p> Signup and view all the answers

<p>The cell wall is non-living and freely permeable, while the cell membrane is living and selectively permeable.</p> Signup and view all the answers

<p>Matrix, organelles, and non-living inclusions like vacuoles and granules</p> Signup and view all the answers

<p>Nuclear membrane, nucleoplasm, nucleolus, and chromatin material</p> Signup and view all the answers

<p>To separate the nucleus from the cytoplasm and control the passage of materials</p> Signup and view all the answers

<p>To produce ribosomes</p> Signup and view all the answers

<p>Darkly stained network of long and fine threads called chromatin threads</p> Signup and view all the answers

<p>To serve as the outer covering of the protoplasm</p> Signup and view all the answers

<p>Nucleoplasm is the part of protoplasm within the nucleus, while cytoplasm is the fluid content of the cell excluding the nucleus</p> Signup and view all the answers

<p>It controls all the vital functions of the cell</p> Signup and view all the answers

<p>exchange of different substances between nucleoplasm and cytoplasm</p> Signup and view all the answers

<p>DNA and proteins</p> Signup and view all the answers

<p>manufacture and storage of important chemical compounds</p> Signup and view all the answers

<p>chromoplasts</p> Signup and view all the answers

<p>storage of starch, proteins, and fats</p> Signup and view all the answers

<p>energy is produced during photosynthesis</p> Signup and view all the answers

<p>involved in pigment synthesis and storage</p> Signup and view all the answers

<p>presence or absence of a nucleus</p> Signup and view all the answers

<p>provides structural support and protection</p> Signup and view all the answers

<p>photosynthesis</p> Signup and view all the answers

<p>exchange of different substances between nucleoplasm and cytoplasm</p> Signup and view all the answers

<p>DNA and proteins</p> Signup and view all the answers

<p>manufacture and storage of important chemical compounds</p> Signup and view all the answers

<p>red, yellow, or orange in color and involved in pigment synthesis and storage</p> Signup and view all the answers

<p>store food prepared in the plant in the form of starch, proteins, and fats</p> Signup and view all the answers

<p>because energy is also produced during photosynthesis</p> Signup and view all the answers

<p>responsible for pigment synthesis and storage and photosynthesis</p> Signup and view all the answers

<p>presence or absence of a true nucleus</p> Signup and view all the answers

<p>selectively permeable, regulating the movement of substances in and out of the cell</p> Signup and view all the answers

<p>provides structural support and protection to the cell</p> Signup and view all the answers

<p>Nucleopores facilitate the exchange of different substances between the nucleoplasm and cytoplasm.</p> Signup and view all the answers

<p>Plastids are responsible for photosynthesis, storage of products like starch, and the synthesis and storage of pigments.</p> Signup and view all the answers

<p>Chromoplasts are pigmented, whereas leucoplasts are colourless or white.</p> Signup and view all the answers

<p>Plant cells have a greater distribution of plastids because they produce energy through photosynthesis, whereas animal cells rely on mitochondria for energy production.</p> Signup and view all the answers

<p>DNA carries all genetic information, which is passed on to the next generation.</p> Signup and view all the answers

<p>The nucleus contains most of the cell's genetic material, in the form of DNA.</p> Signup and view all the answers

<p>Prokaryotes lack a true nucleus, whereas eukaryotes have a true nucleus.</p> Signup and view all the answers

<p>The cell wall provides support, shape, and protection to the cell.</p> Signup and view all the answers

<p>Selectively permeable membranes allow certain substances to pass through while blocking others.</p> Signup and view all the answers

<p>The nuclear region contains the genetic material, whereas the cytoplasm is the region outside the nucleus where metabolic processes occur.</p> Signup and view all the answers

<p>Disc-shaped</p> Signup and view all the answers

<p>Contains photosynthetic enzymes and starch grains</p> Signup and view all the answers

<p>Provides protection</p> Signup and view all the answers

<p>Protein synthesis</p> Signup and view all the answers

<p>Presence of a nuclear membrane</p> Signup and view all the answers

<p>Regulates the movement of materials in and out of the cell</p> Signup and view all the answers

<p>Membrane-bound vesicles that contain chlorophyll</p> Signup and view all the answers

<p>Interconnects grana</p> Signup and view all the answers

<p>Ribosomes synthesize proteins</p> Signup and view all the answers

<p>Protein factory of the cell or Engine of the cell</p> Signup and view all the answers

<p>It stores food, salts, sugar, amino acids, and organic acids, and helps in maintaining turgidity and rigidity of the cell</p> Signup and view all the answers

<p>Tonoplast</p> Signup and view all the answers

<p>In the ribosomes</p> Signup and view all the answers

<p>It occupies 50-90% of the cell volume and helps in maintaining turgidity and rigidity of the cell</p> Signup and view all the answers

<p>Cell sap</p> Signup and view all the answers

<p>It stores nutrients, helps in maintaining turgidity and rigidity of the cell, and is a dump for waste products</p> Signup and view all the answers

<p>Ribosomes function as enzymes or provide support for other cell functions, and are also known as the 'Engine of the cell'. They are responsible for protein synthesis.</p> Signup and view all the answers

<p>Sap vacuoles store salts, sugars, amino acids, organic acids, and some proteins, and also help in maintaining turgidity and rigidity of the cell.</p> Signup and view all the answers

<p>Free ribosomes are found floating in the cytoplasm, while bound ribosomes are attached to the endoplasmic reticulum.</p> Signup and view all the answers

<p>The tonoplast is the membrane that surrounds the sap vacuole and regulates the flow of materials in and out of the vacuole.</p> Signup and view all the answers

<p>The fluid content of a sap vacuole is called cell sap.</p> Signup and view all the answers

<p>Proteins are synthesized inside the cell at the ribosomes.</p> Signup and view all the answers

<p>Sap vacuoles help in osmotic absorption of water by regulating the amount of water in the cell.</p> Signup and view all the answers

<p>Ribosomes are often referred to as the 'protein factory' of the cell or the 'engine of the cell'.</p> Signup and view all the answers

<p>Chloroplasts are usually disc-shaped, and the stroma contains a variety of photosynthetic enzymes and starch grains.</p> Signup and view all the answers

<p>Prokaryotes are organisms whose cells lack a nuclear membrane and the genetic material lies freely in the form of nucleoid, whereas eukaryotes are organisms whose cells have a well-organized nucleus with a nuclear membrane.</p> Signup and view all the answers

<p>The cell wall provides protection to the plant cell.</p> Signup and view all the answers

<p>Ribosomes are the protein builders or protein synthesizers of the cell.</p> Signup and view all the answers

<p>The selective permeability of the plasma membrane allows certain substances to pass through while keeping others out, which is essential for maintaining cellular homeostasis.</p> Signup and view all the answers

<p>Thylakoids are membrane-bound vesicles that are usually stacked in grana and contain the photosynthetic pigment chlorophyll.</p> Signup and view all the answers

<p>The intergranal frets or lamellae are tubular membranes that connect the grana and allow for the exchange of substances between them.</p> Signup and view all the answers

<p>Passive transport occurs through diffusion, whereas active transport requires energy and involves the movement of ions, sugars, amino acids, etc. across the plasma membrane.</p> Signup and view all the answers

<p>osmoregulation and excretion</p> Signup and view all the answers

<p>cell division</p> Signup and view all the answers

<p>division of labour</p> Signup and view all the answers

<p>necessary for growth</p> Signup and view all the answers

<p>helps in replacement of old and worn-out cells</p> Signup and view all the answers

<p>essential for reproduction and birth of young ones</p> Signup and view all the answers

<p>replaces damaged or worn-out cells</p> Signup and view all the answers

<p>division of labour</p> Signup and view all the answers

<p>Osmoregulation and excretion</p> Signup and view all the answers

<p>Cell division</p> Signup and view all the answers

<p>For growth, replacement of old cells, reproduction, and repair</p> Signup and view all the answers

<p>Division of labour</p> Signup and view all the answers

<p>Replacement of old and worn-out cells</p> Signup and view all the answers

<p>Essential for reproduction and birth of young ones</p> Signup and view all the answers

<p>Helps in replacement of old and worn-out cells</p> Signup and view all the answers

<p>Necessary for growth</p> Signup and view all the answers