Cell Structure and Organisation – Vocabulary Flashcards

Vocabulary flashcards covering key cell structures, specialised cells, and organisational concepts from the lecture notes.

Cell

The basic unit of life, consisting of living material called protoplasm enclosed by a membrane.

Protoplasm

All living material within a cell, including the cytoplasm and nucleus.

Cell Surface Membrane

Partially permeable lipid-protein barrier that controls substance movement into and out of the cell.

Cytoplasm

Gel-like substance inside the cell where most chemical reactions and organelles are found.

Nucleus

Double-membraned organelle containing DNA; controls cell activities and is essential for division.

Cell Wall

Fully permeable cellulose layer in plant cells that protects, supports, and maintains cell shape.

Vacuole (Plant)

Large central, sap-filled space that stores substances and maintains turgor pressure.

Vacuole (Animal)

Small, temporary, fluid-filled sac for storage or transport in animal cells.

Chloroplast

Double-membraned organelle containing chlorophyll for absorbing light energy during photosynthesis.

Mitochondrion

Double-membraned organelle where aerobic respiration releases energy for cellular activities.

Ribosome

Tiny organelle (free or on RER) that synthesises proteins from amino acids.

Endoplasmic Reticulum (ER)

Network of membrane-bound spaces involved in synthesis and transport of cell products.

Rough Endoplasmic Reticulum (RER)

ER studded with ribosomes; transports proteins to the Golgi body for secretion.

Smooth Endoplasmic Reticulum (SER)

Tubular ER without ribosomes; synthesises lipids and detoxifies harmful substances.

Golgi Body (Golgi Apparatus)

Stack of flattened membranes that modifies, packages, and directs substances for secretion.

Vesicle

Small membrane sac that transports or stores substances within or outside the cell.

Turgor Pressure

Internal pressure exerted by fluid in the vacuole, keeping plant cells firm.

Photosynthesis

Conversion of light energy to chemical energy (glucose) in chloroplasts.

Aerobic Respiration

Energy-releasing breakdown of glucose using oxygen, occurring in mitochondria.

Detoxification (in SER)

Conversion of harmful chemicals to harmless substances by the smooth ER.

Plant Cell

Eukaryotic cell with a cell wall, chloroplasts, and a large central vacuole.

Animal Cell

Eukaryotic cell lacking a cell wall and chloroplasts; contains small temporary vacuoles.

Tissue

Group of similar cells working together to perform a specific function.

Organ

Structure made of different tissues working together for a particular task.

Organ System

Group of organs cooperating to carry out a major body function.

Cell Differentiation

Process by which stem-derived cells become specialized to perform specific functions.

Red Blood Cell

Biconcave, nucleus-lacking cell containing haemoglobin for oxygen transport.

Haemoglobin

Red pigment in RBCs that binds oxygen, forming oxyhaemoglobin.

Biconcave Shape

Indented disc form of RBCs that increases surface area to volume ratio for gas exchange.

Muscle Cell

Elongated cell rich in mitochondria that contracts to produce movement.

Root Hair Cell

Plant root epidermal cell with long projection for absorbing water and mineral salts.

Surface Area to Volume Ratio

Measure influencing the rate of diffusion; higher ratio speeds transport across membranes.

Osmosis

Net movement of water molecules through a partially permeable membrane from higher to lower water potential.

Active Transport

Energy-requiring movement of substances against their concentration gradient via membrane proteins.