Cell- Biology

Vocabulary flashcards based on lecture notes about cells.

Cell

The fundamental structural and functional unit of all living beings.

Antony van Leeuwenhoek

Dutch scientist who constructed the first microscope using a single biconvex lens (simple microscope).

Robert Hooke

English scientist who developed a microscope using two lenses (compound microscope) and first observed cells in cork.

Cell Theory

States that the cell is the smallest unit of structure and function of all living things, and all cells arise from pre-existing cells, proposed by Schwann and Schleiden.

Matthias Schleiden

German botanist who announced that every plant is made up of a large number of cells.

Theodor Schwann

German zoologist, made similar discoveries in animals. He declared that all animals and plants are composed of cells, which serve as the units of structure and function

Rudolf Virchow

Made an addition to the cell theory by saying that all cells arise from pre-existing cells.

Unicellular Organism

An organism made up of only one cell (e.g., bacteria, yeast, amoeba).

Multicellular Organism

An organism made up of millions or billions of cells (e.g., human beings, mango).

Cell Membrane (Plasma Membrane)

The outer boundary of the cell that regulates the entry and exit of substances.

Cell Wall

A rigid outer layer found in plant cells, made of cellulose, providing shape and support.

Cytoplasm

The semi-liquid substance within the cell membrane, containing various organelles.

Endoplasmic Reticulum (ER)

A network of membranes within the cytoplasm involved in protein and lipid synthesis and distribution.

Ribosomes

Small granules in the cytoplasm or attached to the ER, responsible for protein synthesis.

Mitochondria

Organelles responsible for cell respiration and energy production in the form of ATP; often called the 'powerhouses of the cell'.

Golgi Apparatus

An organelle involved in the secretion of enzymes, hormones, and other substances.

Lysosomes

Vesicles containing digestive enzymes for intracellular digestion; sometimes called 'suicide bags'.

Centrosome

An area in cytoplasm close to nucleus, from which spindle fibres develop during cell division both in mitosis and meiosis. (only in animal cell)

Plastids

Organelles found only in plant cells, including chloroplasts, chromoplasts, and leucoplasts.

Leucoplasts

Colorless plastids that store starch.

Chromoplasts

Variously colored plastids that provide color to petals and fruits.

Chloroplasts

Green plastids containing chlorophyll, responsible for photosynthesis.

Vacuoles

Clear spaces in the cytoplasm filled with water and various substances; large in plant cells.

Nucleus

The control center of the cell, containing DNA and regulating cell functions.

Nucleolus

A structure within the nucleus involved in protein synthesis.

Chromatin Fibers

Thread-like structures in the nucleus that condense into chromosomes during cell division.

Prokaryotic Cell

A cell lacking a well-defined nucleus and other membrane-bound organelles (e.g., bacteria).

Eukaryotic Cell

A cell with a well-defined nucleus and membrane-bound organelles (e.g., plant and animal cells).

Protoplasm

The living substance of a cell, including the cytoplasm and nucleus.

Stem cell

An undifferentiated cell in the embryo or adult, which can undergo unlimited divisions and can give rise to one or several different cell types.