Cell Biology and Organelles

Vocabulary flashcards covering cellular structures, theory, eukaryotic vs. prokaryotic distinctions, and organelle functions based on lecture notes.

Robert Hooke

An English scientist who coined the term 'cells' after observing plant cells under a microscope and went on to develop cell theory.

Cell Theory

The foundational biological theory stating that both plant and animal tissue is composed of cells, cells are the basic unit of all life, and cells only develop from existing cells.

Eukaryotic

Cell type meaning 'true nucleus' characterized by a complex structure with membrane-bound organelles; generally makes up multicellular organisms, with yeast as a unicellular example.

Prokaryotic

Cell type meaning 'before nucleus' characterized by an undivided internal structure without membrane-bound organelles or a nucleus; makes up unicellular organisms.

Compartmentalisation

The provision of distinct environments within a cell by membrane-bound organelles, allowing incompatible metabolic reactions requiring different conditions to occur simultaneously.

Metabolism

All the chemical reactions that occur in a cell, including both the building up and breaking down of molecules.

Cell Ultrastructure

The detailed structures within a cell that can only be seen under a high-power electron microscope.

Organelles

Structures within cells that are specialized to carry out a particular function.

Cell Surface (Plasma) Membrane

A partially and selectively permeable phospholipid bilayer containing proteins that surrounds the external surface of a cell to protect it and regulate molecule movement in and out.

Phospholipid Bilayer

The fundamental structure of the cell surface membrane, composed of two layers of lipids with polar hydrophilic heads and hydrophobic tails.

Cytoplasm

A jelly-like liquid within the cell that acts as the site where all metabolic chemical reactions occur.

Nucleus

Organelle surrounded by a double-membrane nuclear envelope containing genetic material (DNA wound around histone proteins) and the nucleolus.

Nuclear Envelope

A double membrane surrounding the nucleus containing nuclear pores that separates the nucleus from the cytoplasm and regulates molecular movement between them.

Nuclear Pores

Openings in the nuclear envelope that allow molecules such as mRNA to move into and out of the nucleus.

Nucleolus

A dark-staining region inside the nucleus responsible for synthesizing ribosomes.

Mitochondrion

A sausage-shaped organelle surrounded by a double-membrane envelope that carries out aerobic respiration to produce ATP for cellular energy.

Cristae

Folds of the inner mitochondrial membrane containing the enzymes required to speed up aerobic respiration.

Matrix

The fluid-filled interior space bounded by the inner membrane cristae of a mitochondrion, containing mitochondrial DNA and ribosomes.

Vesicles

Membrane-bound sacs surrounded by a single membrane used for storage and transport of materials within or out of cells.

Transport Vesicles

Specific vesicles that carry molecules designated for transport around the inside of the cell.

Secretory Vesicles

Vesicles containing molecules destined to be carried to the cell surface membrane to be released from the cell.

Lysosomes

Specialized single-membrane vesicles containing hydrolytic/digestive enzymes that degrade waste materials, worn-out organelles, and invading pathogens.

Amyloplast

An organelle found in plant cells that contains starch grains as a food source.

Tonoplast

The selective membrane surrounding the large permanent vacuole in plant cells.

Plasmodesmata

Channels of continuous cytoplasm that pass through cell walls to connect adjacent plant cells.

Centrioles

A pair of organelles arranged at right angles located near the nucleus in animal cells.