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Role of the cell membrane in maintaining equilibrium: Regulates nutrient and waste exchange. Maintains homeostasis through selective permeability. Uses active and passive transport to balance ion concentrations. Related Questions: Explain the structural model of the cell membrane and give the roles of the cell membrane. How is the cell wall important in the lifestyle of … Read more
Mesophyll cells – Large surface area for light absorption. Epidermal cells – Protect the plant and aid gas exchange. Neurons – Long extensions for rapid signal transmission. Muscle cells – Elongated for contraction and movement. Red blood cells – Biconcave for efficient oxygen transport. Liver cells – Contain many enzymes for metabolism. Related Questions: Explain … Read more
Specialized structure and function of leaf cells: Mesophyll cells contain chloroplasts for photosynthesis. Epidermal cells form stomata for gas exchange. Vascular tissues transport water and nutrients. Related Questions: Explain the structural model of the cell membrane and give the roles of the cell membrane. How is the cell wall important in the lifestyle of plants? … Read more
An animal cell is a eukaryotic cell with membrane-bound organelles but lacks a cell wall and chloroplasts. Structure and Functions of an Animal Cell Cell Membrane – Controls the movement of substances. Nucleus – Stores DNA and controls cell activities. Mitochondria – Generate ATP through respiration. Endoplasmic Reticulum (RER & SER) – Synthesizes proteins and … Read more
Types of Plastids and Their Roles Plastids are organelles found in plant cells and some protists, playing roles in storage, photosynthesis, and pigment production. Types of Plastids and Their Functions 1. Chloroplasts – Contain chlorophyll and perform photosynthesis, converting sunlight into chemical energy. 2. Chromoplasts – Contain carotenoids (orange, red, yellow pigments), responsible for flower … Read more
Significance of Muscles in the Life of Animals Muscles are specialized tissues responsible for movement, posture, circulation, and essential bodily functions in animals. There are three types of muscles: 1. Skeletal Muscles – Attached to bones and responsible for voluntary movements (e.g., walking, lifting objects). 2. Cardiac Muscles – Found in the heart, involuntary, and … Read more
The Smooth Endoplasmic Reticulum (SER) is a network of membrane-bound tubules involved in various cellular processes. Cells rich in SER are highly specialized for specific functions. Functions of SER-Rich Cells 1. Lipid and Steroid Hormone Synthesis – SER is responsible for producing lipids, phospholipids, and steroid hormones like estrogen and testosterone. Cells in the ovaries … Read more
The cell wall is a rigid, protective structure surrounding the plasma membrane in plant cells, fungi, and some bacteria. It provides mechanical strength, protection, and regulates water intake. Composition of the Plant Cell Wall The primary cell wall is made of cellulose, providing flexibility and strength. The secondary cell wall (in mature cells) contains lignin, … Read more
The cell membrane is a selectively permeable structure that surrounds the cell, maintaining its integrity while regulating the movement of substances. The most widely accepted model of the cell membrane is the fluid mosaic model, proposed by Singer and Nicolson in 1972. Structural Model of the Cell Membrane (Fluid Mosaic Model) The cell membrane is … Read more