Cell: The Unit of Life

These flashcards cover key concepts and definitions related to the unit of life and the various cell types and tissues in living organisms.

Cell

The fundamental structural and functional unit of all living beings, capable of independent existence.

Protoplasm

The living substance of a cell, consisting of cytoplasm and nucleus.

Plasma Membrane

The thin, flexible, living membrane that surrounds the cell, regulating entry and exit of substances.

Cell Wall

A rigid, non-living structure found in plant cells, composed mainly of cellulose for protection and support.

Mitochondria

Sausage-shaped organelles known as the powerhouses of the cell, responsible for producing ATP and energy.

Chloroplasts

Organelles found in plant cells containing chlorophyll, involved in photosynthesis.

Nucleus

The largest organelle in the cell that regulates cell functions and contains genetic material.

Chromatin

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

Ribosomes

The sites of protein synthesis in cells, made up of RNA.

Lysosomes

Membranous sacs containing digestive enzymes, involved in intracellular digestion and waste removal.

Prokaryotic Cells

Cells without a well-defined nucleus, such as bacteria.

Eukaryotic Cells

Cells with a well-defined nucleus and membrane-bound organelles, such as plant and animal cells.

Cell Theory

A fundamental principle stating that all living things are composed of cells, the cell is the basic unit of life, and all cells arise from pre-existing cells.

Meristematic Tissue

Plant tissue made up of actively dividing cells, found at growing tips.

Permanent Tissue

Plant tissue that has lost the ability to divide and has taken on a permanent function.

Xylem

The vascular tissue responsible for the upward transport of water and dissolved minerals in plants.

Phloem

The vascular tissue responsible for the transport of food from leaves to other parts of the plant.

Epithelial Tissue

A protective tissue forming continuous sheets covering body surfaces and lining cavities.

Connective Tissue

Tissue that supports, binds, and connects other tissues and organs in the body.

Muscle Tissue

Tissue responsible for movement in the body, which can contract and relax.

Nervous Tissue

Tissue that makes up the nervous system, consisting of neurons that transmit impulses.