Cell Structure and Function

These flashcards cover key vocabulary and concepts related to cell structure and function.

Cell Wall

A rigid outer layer found in plant cells that is freely permeable and allows substances to enter and leave the cell without hindrance.

Cytoplasm

A semi-liquid substance within the cell membrane where many chemical reactions occur and all organelles are embedded.

Endoplasmic Reticulum (ER)

An irregular network of double membranes that serves as a supportive framework and pathway for the distribution of materials within the cell.

Ribosomes

Small granules that serve as the sites for protein synthesis within the cell.

Mitochondria

Double-walled organelles known as the 'powerhouses of the cell,' where cell respiration occurs and energy is produced in the form of ATP.

Golgi Apparatus

An organelle involved in the secretion and packaging of enzymes and hormones, characterized by stacks of flattened membrane sacs.

Lysosomes

Vesicles that contain digestive enzymes, responsible for breaking down waste materials and cellular debris.

Centrosome

A structure found only in animal cells that is involved in cell division; it contains two centrioles.

Plastids

Organelles found in plant cells that are responsible for the storage of food and coloration, including chloroplasts, chromoplasts, and leucoplasts.

Nucleus

The control center of the cell that regulates and coordinates various life processes, containing chromatin and nucleoli.

Prokaryotic Cells

Cells that lack a well-defined nucleus and membrane-bound organelles, such as bacteria.

Eukaryotic Cells

Cells that contain a true nucleus and membrane-bound organelles, including all plant and animal cells.

Chromatin

Thread-like structures within the nucleus that condense to form chromosomes during cell division.

Vacuoles

Clear spaces within the cytoplasm, usually larger in plant cells, that store water and other substances.

Granules

Small particles found in the cytoplasm that contain food materials such as starch and fats.

ATP (Adenosine Triphosphate)

An energy-rich compound produced in mitochondria that is used in various metabolic functions of the cell.

Cell Wall

A rigid outer layer found in plant cells that provides structural support and protection. It is composed mainly of cellulose and allows substances to pass freely in and out of the cell.

Cytoplasm

A semi-liquid, jelly-like substance that fills the interior of the cell, containing all organelles. It is the site of numerous biochemical reactions essential for cell function.

Endoplasmic Reticulum (ER)

An extensive network of membranes that plays a crucial role in the synthesis of proteins and lipids. The rough ER is studded with ribosomes and is involved in protein synthesis, while the smooth ER is involved in lipid synthesis and detoxification.

Ribosomes

Small, non-membrane-bound organelles that can be found either floating freely in the cytoplasm or attached to the rough ER. They are essential for translating mRNA into proteins.

Mitochondria

Double-walled organelles known as the 'powerhouses of the cell.' They convert biochemical energy from food into adenosine triphosphate (ATP) through the process of cellular respiration.

Golgi Apparatus

A series of stacked, flattened membrane sacs that modify, sort, and package proteins and lipids for secretion or for use within the cell. It is also involved in the process of glycosylation.

Lysosomes

Membrane-bound vesicles containing digestive enzymes necessary for breaking down and recycling cellular waste, damaged organelles, and pathogens.

Centrosome

An organelle found only in animal cells, acting as the main microtubule organizing center. It consists of two centrioles that are vital for cell division, facilitating proper chromosome alignment.

Plastids

Organelles found in plant cells that are involved in the synthesis and storage of food. Chloroplasts, a type of plastid, are responsible for photosynthesis, while chromoplasts give color to fruits and flowers.

Nucleus

The control center of the cell that houses the cell's genetic material in the form of DNA. It coordinates activities such as growth, metabolism, and reproduction, and contains structures like nucleoli where ribosome production occurs.

Prokaryotic Cells

Simple, unicellular organisms that lack a defined nucleus or membrane-bound organelles. Examples include bacteria and archaea, which have DNA concentrated in a nucleoid region.

Eukaryotic Cells

More complex cells that possess a defined nucleus and membrane-bound organelles, including plants, animals, fungi, and protists. They generally have a larger size and a more complex structure compared to prokaryotic cells.

Chromatin

A complex of DNA and protein found in the nucleus, which condenses to form chromosomes during cell division. Chromatin plays a role in regulating gene expression.

Vacuoles

Large, membrane-bound sacs within the cytoplasm that store various substances. In plant cells, vacuoles can occupy a significant volume, storing water, nutrients, and waste products.

Granules

Small, membrane-bound particles found in the cytoplasm that store essential nutrients, such as starches or lipids, providing a reserve of energy for the cell.