Name: cell organization in prokaryotes and eukaryotes
Uploaded: 2025-06-12T09:28:11.000Z
Duration: 1 min 28 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Biology

from-molecules-to-organisms-structures-and-processes

From Molecules to Organisms- Structures and Processes

LS.Bio.1.4

Prokaryotic vs. Eukaryotic Cells

تختلف الخلايا بدائية النواة وحقيقية النواة اختلافا كبيرا في التركيب والوظيفة. الخلايا بدائية النواة ، مثل البكتيريا والعتائق ، بسيطة وتفتقر إلى العضيات المرتبطة بالغشاء ، بما في ذلك النواة. عادة ما تكون أحادية الخلية وصغيرة ، ويتراوح طولها من 0.1 إلى 5.0 ميكرومتر. تتكون جينوماتهم من جزيء DNA دائري واحد في منطقة النواة. تحتوي بدائيات النوى على 70S ريبوسومات ، وهي أصغر مقارنة بالريبوسومات حقيقية النواة. لديهم هياكل داخلية أبسط ، والتي تسمح بالنمو السريع والتكاثر ، غالبا من خلال الانشطار الثنائي. على العكس من ذلك ، فإن الخلايا حقيقية النواة ، الموجودة في النباتات والفطريات والأوليات ، أكثر تعقيدا. تحتوي على عضيات مرتبطة بالغشاء مثل النواة والميتوكوندريا والشبكة الإندوبلازمية التي تسمح بتجزئة الوظائف الخلوية. لديهم جينومات كبيرة مصنوعة من الحمض النووي الخطي المخزنة في النواة. يبلغ قياس الخلايا حقيقية النواة من 10 إلى 100 ميكرومتر أو أكثر وقد تشكل كائنات متعددة الخلايا ذات أنواع خلايا متخصصة للوظائف البيولوجية المعقدة. لديهم أيضا ريبوسومات 80S الأكبر ، مما يعكس آلية تخليق البروتين المعقدة.

الخلايا بدائية النواة مقابل الخلايا حقيقية النواة

&#1578;&#1605;&#1579;&#1604; &#1582;&#1604;&#1575;&#1610;&#1575; &#1576;&#1583;&#1575;&#1574;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; &#1608;&#1581;&#1602;&#1610;&#1602;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; &#1606;&#1608;&#1593;&#1610;&#1606; &#1571;&#1587;&#1575;&#1587;&#1610;&#1610;&#1606; &#1605;&#1606; &#1575;&#1604;&#1578;&#1606;&#1592;&#1610;&#1605; &#1575;&#1604;&#1582;&#1604;&#1608;&#1610;&#1548; &#1610;&#1582;&#1578;&#1604;&#1601;&#1575;&#1606; &#1576;&#1588;&#1603;&#1604; &#1603;&#1576;&#1610;&#1585; &#1601;&#1610; &#1575;&#1604;&#1607;&#1610;&#1603;&#1604; &#1608;&#1575;&#1604;&#1578;&#1593;&#1602;&#1610;&#1583; &#1608;&#1575;&#1604;&#1608;&#1592;&#1610;&#1601;&#1577;. &#1607;&#1584;&#1607; &#1575;&#1604;&#1601;&#1585;&#1608;&#1602;&#1575;&#1578; &#1607;&#1610; &#1575;&#1604;&#1571;&#1587;&#1575;&#1587; &#1604;&#1604;&#1578;&#1606;&#1608;&#1593; &#1575;&#1604;&#1576;&#1610;&#1608;&#1604;&#1608;&#1580;&#1610; &#1575;&#1604;&#1584;&#1610; &#1606;&#1585;&#1575;&#1607; &#1593;&#1576;&#1585; &#1605;&#1580;&#1575;&#1604;&#1575;&#1578; &#1575;&#1604;&#1581;&#1610;&#1575;&#1577;.
&#1582;&#1589;&#1575;&#1574;&#1589; &#1582;&#1604;&#1575;&#1610;&#1575; &#1576;&#1583;&#1575;&#1574;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609;
&#1582;&#1604;&#1575;&#1610;&#1575; &#1576;&#1583;&#1575;&#1574;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609;&#1548; &#1575;&#1604;&#1578;&#1610; &#1578;&#1605;&#1579;&#1604;&#1607;&#1575; &#1575;&#1604;&#1576;&#1603;&#1578;&#1610;&#1585;&#1610;&#1575; &#1608;&#1575;&#1604;&#1593;&#1578;&#1575;&#1574;&#1602;&#1548; &#1607;&#1610; &#1582;&#1604;&#1575;&#1610;&#1575; &#1576;&#1587;&#1610;&#1591;&#1577;&#1612; &#1605;&#1606; &#1581;&#1610;&#1579;&#1615; &#1575;&#1604;&#1607;&#1610;&#1603;&#1604;&#1616; &#1608;&#1604;&#1575; &#1578;&#1581;&#1578;&#1608;&#1610; &#1593;&#1604;&#1609; &#1593;&#1590;&#1610;&#1575;&#1578; &#1605;&#1581;&#1575;&#1591;&#1577; &#1576;&#1594;&#1588;&#1575;&#1569;&#1548; &#1576;&#1605;&#1575; &#1601;&#1610; &#1584;&#1604;&#1603; &#1575;&#1604;&#1606;&#1608;&#1575;&#1577;. &#1578;&#1578;&#1603;&#1608;&#1606; &#1605;&#1575;&#1583;&#1578;&#1607;&#1575; &#1575;&#1604;&#1608;&#1585;&#1575;&#1579;&#1610;&#1577; &#1605;&#1606; &#1580;&#1586;&#1610;&#1569; &#1608;&#1575;&#1581;&#1583; &#1583;&#1575;&#1574;&#1585;&#1610; &#1605;&#1606; &#1575;&#1604;&#1581;&#1605;&#1590; &#1575;&#1604;&#1606;&#1608;&#1608;&#1610; &#1601;&#1610; &#1605;&#1606;&#1591;&#1602;&#1577; &#1575;&#1604;&#1606;&#1610;&#1608;&#1603;&#1604;&#1610;&#1608;&#1583;&#1548; &#1594;&#1610;&#1585; &#1605;&#1581;&#1575;&#1591; &#1576;&#1594;&#1588;&#1575;&#1569; &#1606;&#1608;&#1608;&#1610;. &#1593;&#1575;&#1583;&#1577; &#1605;&#1575; &#1578;&#1603;&#1608;&#1606; &#1582;&#1604;&#1575;&#1610;&#1575; &#1576;&#1583;&#1575;&#1574;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; &#1589;&#1594;&#1610;&#1585;&#1577; &#1575;&#1604;&#1581;&#1580;&#1605;&#1548; &#1581;&#1610;&#1579; &#1578;&#1578;&#1585;&#1575;&#1608;&#1581; &#1605;&#1606; 0.1 &#1573;&#1604;&#1609; 5.0 &#1605;&#1610;&#1603;&#1585;&#1608;&#1605;&#1578;&#1585;&#1548; &#1608;&#1607;&#1610; &#1601;&#1610; &#1575;&#1604;&#1594;&#1575;&#1604;&#1576; &#1608;&#1581;&#1610;&#1583;&#1577; &#1575;&#1604;&#1582;&#1604;&#1610;&#1577;. &#1593;&#1604;&#1609; &#1575;&#1604;&#1585;&#1594;&#1605; &#1605;&#1606; &#1576;&#1587;&#1575;&#1591;&#1578;&#1607;&#1575;&#1548; &#1601;&#1573;&#1606;&#1607;&#1575; &#1578;&#1592;&#1607;&#1585; &#1606;&#1605;&#1608;&#1611;&#1575; &#1608;&#1578;&#1603;&#1575;&#1579;&#1585;&#1611;&#1575; &#1601;&#1593;&#1575;&#1604;&#1611;&#1575;&#1548; &#1608;&#1594;&#1575;&#1604;&#1576;&#1611;&#1575; &#1605;&#1575; &#1578;&#1606;&#1602;&#1587;&#1605; &#1576;&#1587;&#1585;&#1593;&#1577; &#1605;&#1606; &#1582;&#1604;&#1575;&#1604; &#1575;&#1604;&#1575;&#1606;&#1602;&#1587;&#1575;&#1605; &#1575;&#1604;&#1579;&#1606;&#1575;&#1574;&#1610;. &#1575;&#1604;&#1585;&#1610;&#1576;&#1608;&#1587;&#1608;&#1605;&#1575;&#1578; &#1601;&#1610; &#1582;&#1604;&#1575;&#1610;&#1575; &#1576;&#1583;&#1575;&#1574;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; &#1576;&#1581;&#1580;&#1605; 70S&#1548; &#1571;&#1589;&#1594;&#1585; &#1608;&#1571;&#1576;&#1587;&#1591; &#1605;&#1606; &#1606;&#1592;&#1610;&#1585;&#1575;&#1578;&#1607;&#1575; &#1601;&#1610; &#1582;&#1604;&#1575;&#1610;&#1575; &#1581;&#1602;&#1610;&#1602;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609;&#1548; &#1573;&#1604;&#1575; &#1571;&#1606;&#1607;&#1575; &#1603;&#1575;&#1601;&#1610;&#1577;&#1612; &#1604;&#1578;&#1604;&#1576;&#1610;&#1577;&#1616; &#1575;&#1581;&#1578;&#1610;&#1575;&#1580;&#1575;&#1578;&#1616;&#1607;&#1575; &#1605;&#1606; &#1578;&#1582;&#1604;&#1610;&#1602; &#1575;&#1604;&#1576;&#1585;&#1608;&#1578;&#1610;&#1606;.
&#1582;&#1589;&#1575;&#1574;&#1589; &#1582;&#1604;&#1575;&#1610;&#1575; &#1581;&#1602;&#1610;&#1602;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609;
&#1576;&#1575;&#1604;&#1605;&#1602;&#1575;&#1576;&#1604;&#1548; &#1582;&#1604;&#1575;&#1610;&#1575; &#1581;&#1602;&#1610;&#1602;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609;&#1548; &#1575;&#1604;&#1605;&#1608;&#1580;&#1608;&#1583;&#1577; &#1601;&#1610; &#1575;&#1604;&#1601;&#1591;&#1585;&#1610;&#1575;&#1578; &#1608;&#1575;&#1604;&#1591;&#1581;&#1575;&#1604;&#1576; &#1608;&#1575;&#1604;&#1571;&#1608;&#1604;&#1610;&#1575;&#1578; &#1608;&#1575;&#1604;&#1603;&#1575;&#1574;&#1606;&#1575;&#1578; &#1575;&#1604;&#1581;&#1610;&#1577; &#1575;&#1604;&#1571;&#1582;&#1585;&#1609;&#1548; &#1607;&#1610; &#1582;&#1604;&#1575;&#1610;&#1575; &#1605;&#1593;&#1602;&#1583;&#1577; &#1604;&#1604;&#1594;&#1575;&#1610;&#1577;. &#1578;&#1578;&#1605;&#1610;&#1586; &#1576;&#1608;&#1580;&#1608;&#1583; &#1593;&#1590;&#1610;&#1575;&#1578; &#1605;&#1581;&#1575;&#1591;&#1577; &#1576;&#1594;&#1588;&#1575;&#1569; &#1605;&#1579;&#1604; &#1575;&#1604;&#1606;&#1608;&#1575;&#1577;&#1548; &#1575;&#1604;&#1578;&#1610; &#1578;&#1581;&#1578;&#1608;&#1610; &#1593;&#1604;&#1609; &#1575;&#1604;&#1581;&#1605;&#1590; &#1575;&#1604;&#1606;&#1608;&#1608;&#1610; &#1575;&#1604;&#1582;&#1591;&#1610; &#1575;&#1604;&#1605;&#1606;&#1592;&#1605; &#1601;&#1610; &#1575;&#1604;&#1603;&#1585;&#1608;&#1605;&#1608;&#1587;&#1608;&#1605;&#1575;&#1578;. &#1578;&#1578;&#1590;&#1605;&#1606; &#1575;&#1604;&#1593;&#1590;&#1610;&#1575;&#1578; &#1575;&#1604;&#1571;&#1582;&#1585;&#1609; &#1605;&#1579;&#1604; &#1575;&#1604;&#1605;&#1610;&#1578;&#1608;&#1603;&#1608;&#1606;&#1583;&#1585;&#1610;&#1575; &#1608;&#1575;&#1604;&#1588;&#1576;&#1603;&#1577; &#1575;&#1604;&#1573;&#1606;&#1583;&#1608;&#1576;&#1604;&#1575;&#1586;&#1605;&#1610;&#1577; &#1608;&#1580;&#1607;&#1575;&#1586; &#1594;&#1608;&#1604;&#1580;&#1610;&#1548; &#1605;&#1605;&#1575; &#1610;&#1587;&#1605;&#1581; &#1576;&#1578;&#1602;&#1587;&#1610;&#1605; &#1608;&#1592;&#1575;&#1574;&#1601; &#1575;&#1604;&#1582;&#1604;&#1575;&#1610;&#1575;&#1548; &#1608; &#1610;&#1593;&#1586;&#1586; &#1575;&#1604;&#1603;&#1601;&#1575;&#1569;&#1577; &#1608;&#1575;&#1604;&#1578;&#1582;&#1589;&#1589;. &#1578;&#1578;&#1605;&#1610;&#1586; &#1575;&#1604;&#1582;&#1604;&#1575;&#1610;&#1575; &#1581;&#1602;&#1610;&#1602;&#1610;&#1577; &#1575;&#1604;&#1606;&#1608;&#1575;&#1577; &#1576;&#1571;&#1606;&#1607;&#1575; &#1571;&#1603;&#1576;&#1585; &#1581;&#1580;&#1605;&#1575;&#1611; &#1576;&#1603;&#1579;&#1610;&#1585;&#1548; &#1581;&#1610;&#1579; &#1610;&#1578;&#1585;&#1575;&#1608;&#1581; &#1581;&#1580;&#1605;&#1607;&#1575; &#1576;&#1610;&#1606; 10 &#1608; 100 &#1605;&#1610;&#1603;&#1585;&#1608;&#1605;&#1578;&#1585; &#1571;&#1608; &#1571;&#1603;&#1579;&#1585;&#1548; &#1608;&#1610;&#1605;&#1603;&#1606;&#1607;&#1575; &#1571;&#1606; &#1578;&#1588;&#1603;&#1604; &#1603;&#1575;&#1574;&#1606;&#1575;&#1578; &#1605;&#1578;&#1593;&#1583;&#1583;&#1577; &#1575;&#1604;&#1582;&#1604;&#1575;&#1610;&#1575; &#1584;&#1575;&#1578; &#1571;&#1606;&#1608;&#1575;&#1593; &#1582;&#1604;&#1575;&#1610;&#1575; &#1605;&#1578;&#1582;&#1589;&#1589;&#1577;. &#1578;&#1593;&#1603;&#1587; &#1575;&#1604;&#1585;&#1610;&#1576;&#1608;&#1587;&#1608;&#1605;&#1575;&#1578; &#1575;&#1604;&#1571;&#1603;&#1576;&#1585; &#1576;&#1581;&#1580;&#1605; 80S &#1570;&#1604;&#1610;&#1577; &#1578;&#1582;&#1604;&#1610;&#1602; &#1575;&#1604;&#1576;&#1585;&#1608;&#1578;&#1610;&#1606; &#1575;&#1604;&#1571;&#1603;&#1579;&#1585; &#1578;&#1602;&#1583;&#1605;&#1611;&#1575;&#1548; &#1608;&#1575;&#1604;&#1578;&#1610; &#1578;&#1583;&#1593;&#1605; &#1605;&#1578;&#1591;&#1604;&#1576;&#1575;&#1578; &#1607;&#1610;&#1603;&#1604;&#1607;&#1575; &#1575;&#1604;&#1605;&#1593;&#1602;&#1583; &#1608;&#1608;&#1592;&#1575;&#1574;&#1601;&#1607;&#1575;.
&#1575;&#1604;&#1570;&#1579;&#1575;&#1585; &#1575;&#1604;&#1608;&#1592;&#1610;&#1601;&#1610;&#1577; &#1608;&#1575;&#1604;&#1578;&#1591;&#1608;&#1585;&#1610;&#1577;
&#1578;&#1578;&#1610;&#1581; &#1607;&#1584;&#1607; &#1575;&#1604;&#1601;&#1585;&#1608;&#1602;&#1575;&#1578; &#1575;&#1604;&#1571;&#1587;&#1575;&#1587;&#1610;&#1577; &#1601;&#1610; &#1607;&#1610;&#1603;&#1604; &#1608;&#1578;&#1606;&#1592;&#1610;&#1605; &#1575;&#1604;&#1582;&#1604;&#1575;&#1610;&#1575; &#1604;&#1576;&#1603;&#1578;&#1610;&#1585;&#1610;&#1575; &#1576;&#1583;&#1575;&#1574;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; &#1575;&#1604;&#1575;&#1586;&#1583;&#1607;&#1575;&#1585; &#1601;&#1610; &#1576;&#1610;&#1574;&#1575;&#1578; &#1605;&#1578;&#1606;&#1608;&#1593;&#1577; &#1605;&#1593; &#1602;&#1583;&#1585;&#1577; &#1587;&#1585;&#1610;&#1593;&#1577; &#1593;&#1604;&#1609; &#1575;&#1604;&#1578;&#1603;&#1610;&#1601;. &#1576;&#1575;&#1604;&#1605;&#1602;&#1575;&#1576;&#1604;&#1548; &#1578;&#1583;&#1593;&#1605; &#1582;&#1604;&#1575;&#1610;&#1575; &#1581;&#1602;&#1610;&#1602;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; &#1578;&#1591;&#1608;&#1610;&#1585; &#1575;&#1604;&#1571;&#1606;&#1587;&#1580;&#1577; &#1608;&#1575;&#1604;&#1571;&#1606;&#1592;&#1605;&#1577; &#1575;&#1604;&#1605;&#1578;&#1582;&#1589;&#1589;&#1577; &#1601;&#1610; &#1575;&#1604;&#1603;&#1575;&#1574;&#1606;&#1575;&#1578; &#1605;&#1578;&#1593;&#1583;&#1583;&#1577; &#1575;&#1604;&#1582;&#1604;&#1575;&#1610;&#1575;. &#1610;&#1605;&#1579;&#1604; &#1578;&#1602;&#1587;&#1610;&#1605; &#1575;&#1604;&#1608;&#1592;&#1575;&#1574;&#1601; &#1608;&#1586;&#1610;&#1575;&#1583;&#1577; &#1578;&#1593;&#1602;&#1610;&#1583; &#1582;&#1604;&#1575;&#1610;&#1575; &#1581;&#1602;&#1610;&#1602;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; &#1578;&#1602;&#1583;&#1605;&#1611;&#1575; &#1578;&#1591;&#1608;&#1585;&#1610;&#1611;&#1575; &#1603;&#1576;&#1610;&#1585;&#1611;&#1575;&#1548; &#1605;&#1605;&#1575; &#1610;&#1587;&#1605;&#1581; &#1576;&#1575;&#1604;&#1593;&#1605;&#1604;&#1610;&#1575;&#1578; &#1575;&#1604;&#1576;&#1610;&#1608;&#1604;&#1608;&#1580;&#1610;&#1577; &#1575;&#1604;&#1605;&#1593;&#1602;&#1583;&#1577; &#1608;&#1575;&#1585;&#1578;&#1601;&#1575;&#1593; &#1605;&#1587;&#1578;&#1608;&#1610;&#1575;&#1578; &#1575;&#1604;&#1578;&#1606;&#1592;&#1610;&#1605; &#1575;&#1604;&#1603;&#1575;&#1574;&#1606;&#1575;&#1578;&#1610;.

&#1578;&#1605;&#1579;&#1604; &#1582;&#1604;&#1575;&#1610;&#1575; &#1576;&#1583;&#1575;&#1574;&#1610;&#1575;&#1578; &#1575;&#1604;&#1606;&#1608;&#1609; ...

Education

JoVE Core

Microbiology

علم الأحياء الدقيقة

Unit

وحدة

Microbial Cell Structure and Function        

تركيب الخلية الميكروبية ووظائفها

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

cell organization in prokaryotes and eukaryotes

Prokaryotic and eukaryotic cells show two major patterns of cell organization. These differences shape the structure, size, and function of living things across the domains of life.

Prokaryotic cells, such as bacteria and archaea, are simple in structure. They do not have a nucleus or other membrane-bound organelles. Their DNA is usually a single circular molecule found in the nucleoid region, which is not surrounded by a nuclear membrane. Prokaryotes are usually very small, about 0.1 to 5.0 micrometers, and they are almost always unicellular.

Even with this simple design, prokaryotes grow and reproduce efficiently. Many divide quickly by binary fission, a form of cell division that makes two new cells. They also contain 70S ribosomes, which are smaller than the ribosomes found in eukaryotic cells and still support protein synthesis.

Eukaryotic cells are more complex and are found in fungi, algae, protozoa, and other protists. They have a nucleus that contains linear DNA arranged into chromosomes. They also have membrane-bound organelles such as mitochondria, the endoplasmic reticulum, and the Golgi apparatus. These internal compartments help separate tasks and make cell functions more efficient.

Eukaryotic cells are much larger, often measuring 10 to 100 micrometers or more. They can also form multicellular organisms with specialized cell types. Their 80S ribosomes are larger than prokaryotic ribosomes and support the protein production needed for this more complex organization.

These differences help explain why prokaryotes can adapt quickly in many environments. Eukaryotic cells, in contrast, support specialized tissues and body systems in multicellular life. Their compartmentalized structure is an important evolutionary step that allows more complex biological processes.

Cell Organization in Prokaryotes and Eukaryotes

cell-organization-in-prokaryotes-and-eukaryotes

prokaryotic vs. eukaryotic cells

Prokaryotic and eukaryotic cells show two major patterns of cell organization. These differences shape the structure, size, and function of living things across the domains of life. Prokaryotic cells, such as bacteria and archaea, are simple in structure. They do not have a nucleus or other membrane-bound organelles. Their DNA is usually a single circular molecule found in the nucleoid region, which is not surrounded by a nuclear membrane. Prokaryotes are usually very small, about 0.1 to 5.0...

microbial morphologies 

Microbial Shapes and Cell Forms

Microbial shapes and cell forms help bacteria, archaea, and eukaryotic microbes survive in many environments. Cell shape affects how these organisms grow, take up nutrients, and handle waste. It also reflects the link between structure and function. Among bacteria, cocci and bacilli are the most common shapes. Cocci are spherical cells, and they may appear alone or in pairs called diplococci, chains called streptococci, clusters called staphylococci, or groups of four called tetrads. Bacilli...

bacterial cell wall 

Gram-Positive and Gram-Negative Walls

Bacterial cell walls give bacteria their shape and help protect them from osmotic stress. This rigid but flexible layer surrounds the plasma membrane and supports cellular integrity. Its main building block is peptidoglycan, a mesh-like polymer that adds strength while still allowing some flexibility. Peptidoglycan is made of alternating N-acetylglucosamine, or NAG, and N-acetylmuramic acid, or NAM. Short amino acid chains connect these sugar units and help form the strong network. The...

archaeal cell wall

Archaeal Cell Wall Types and Functions

Archaeal cell walls protect archaea and help them survive in extreme environments. Unlike bacterial cell walls, they do not have the peptidoglycan layer found in most bacteria. Instead, archaea use a range of materials, including proteins, polysaccharides, and pseudomurein, to build their outer layer. The most common archaeal cell wall is the S-layer, or surface layer. It is made of tightly packed protein or glycoprotein units that form a crystalline lattice. These repeating patterns can make...

peptidoglycan synthesis

Building the Bacterial Cell Wall

Peptidoglycan builds the bacterial cell wall and gives the cell its shape and strength. It is a mesh-like polymer around the bacterial plasma membrane. The polymer is made of repeating sugar units, N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM), linked by β-1,4 glycosidic bonds. Short peptide chains cross-link the sugar chains and make the wall more rigid. Peptidoglycan biosynthesis starts in the cytoplasm with soluble precursors. Uridine diphosphate, or UDP, binds to NAG and NAM to...

plasma membrane in bacteria and archaea

Bacterial vs Archaeal Membrane Lipids

Bacterial and archaeal plasma membranes control what enters and leaves the cell. They also help maintain cell integrity. Although both membranes do the same basic job, their structures are different because bacteria and archaea face different environmental demands. Bacterial plasma membranes are mainly made of phospholipids. These lipids have fatty acid chains linked to a glycerol backbone by ester bonds. They form a bilayer, with hydrophilic glycerol-phosphate heads facing outward and...

outer layers of the cell envelope

Capsules, Slime Layers, and S-Layers

Capsules, slime layers, and S-layers are outer coverings on prokaryotic cells. These layers help bacteria and archaea survive, attach to surfaces, and interact with their environment. They are often made of polysaccharides, polypeptides, proteins, or glycoproteins. Capsules are tightly bound and highly organized layers that stick firmly to the bacterial cell wall. They are usually made of polysaccharides, although some are made of polypeptides. A capsule protects cells from dehydration and can...

flagella and motility in bacteria

Bacterial Flagella as Tiny Rotary Motors

Bacterial flagella are thread-like structures that help cells move and respond to their surroundings. They extend from the cell envelope and support both motility and chemotaxis, which is the ability to move in response to chemical signals. Their design shows how bacteria use specialized structures to survive in different environments. A flagellum has three main parts: the filament, the hook, and the basal body. The filament is the long, helical part made of repeating flagellin protein...

fimbriae, pili, and axial filaments

How Bacteria Stick, Share Genes, and Move

Fimbriae, pili, and axial filaments are bacterial surface structures that help cells attach, exchange genes, and move. These hairlike appendages are made mainly of pilin protein. They support bacterial survival in different environments and can also increase pathogenicity. Fimbriae are fine, filament-like structures that are densely packed on the bacterial surface. They are about 2 to 10 nanometers wide and help bacteria attach to nonliving surfaces and to host tissues. This adhesion is an...

cell inclusions

Prokaryotic Cell Storage Inclusions

Prokaryotic cell storage inclusions help bacteria store nutrients, manage energy, and adapt to changing environments. These inclusions let cells survive when food, phosphate, sulfur, light, or oxygen levels change. They are important examples of how simple cells can still have highly specialized structures. Some inclusions store carbon. Poly-β-hydroxybutyric acid, or PHB, forms granules that act as a long-term carbon and energy reserve. Glycogen granules also store carbon, but they provide a...

endospores and sporulation

How Bacteria Survive with Endospores

Endospores help some bacteria survive harsh conditions. These dormant cells are made mainly by Gram-positive bacteria such as Bacillus and Clostridium. They are highly resistant to heat, ultraviolet and ionizing radiation, drying, and toxic chemicals. In rare cases, endospore-like structures have also been seen in some Gram-negative bacteria, including Coxiella burnetii and Sporosarcina ureae, as well as in other species exposed to extreme conditions. Sporulation begins when bacteria face...

nucleoid

How Prokaryotes Organize DNA

Prokaryotes organize their DNA in the nucleoid, a distinct region where genetic material and associated proteins are packed. Because prokaryotic cells do not have a membrane-bound nucleus, the nucleoid helps keep DNA organized and available for cell activities. In most bacteria and archaea, the DNA is a single, circular, double-stranded molecule that is tightly compacted by supercoiling and protein interactions. Nucleoid-associated proteins, or NAPs, help shape and maintain this DNA region.

surface appendages of archaea

Archaeal Pili and Archaella in Action

Archaeal pili and archaella help archaea survive, attach, and move in challenging environments. These surface appendages support adhesion, biofilm formation, and motility. They give archaeal cells key advantages in habitats that can be extreme. Pili are filament-like structures made from pilin protein subunits. Their main role is adhesion, which means helping cells stick to surfaces. They also support biofilm formation, where cells live in a shared, surface-attached community. Some pili are...

key terms and concepts

Compare prokaryotic and eukaryotic cell organization, from nuclei and organelles to DNA shape, size, ribosomes, and cell division in grades 9–12.

Cell Organization in Prokaryotes and Eukaryotes | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

Virginia  Standards of Learning

HIgh School

BIO.3

BIO.3.b

BIO.4

BIO.4.c

BIO.6

BIO.6.a

Life Science

LS.2

LS.2.c

new-york-state-science-learning-standards

New York State Science Learning Standards

Middle School

Earth and Space Sciences

Space Systems

MS-ESS1-1

Minnesota Academic Standards in Science

Earth and Space Science

1.1.1 Earth’s Place in the Universe

4.2.2

south-carolina-college-and-career-ready-science-standards

South Carolina College and Career Ready Science Standards

Earth's Place in the Universe

8-ESS1-1

8-ESS1-2

8-ESS1-3

Compounds Essential to Human Function

The human body is composed of cells that are fundamentally made up of several different molecules. These molecules are essential to carry out all ...

Macromolecules

Biomolecules
Organisms contain a wide variety of organic molecules with numerous functions which depend on the chemical structures and properties of these ...

Solution Preparation
ExpandCAUTION: It is important to always use care when handling reagents. For example, iodine will stain clothes and skin so wear ...

Identifying Macromolecules with Indicator Solutions
ExpandHYPOTHESES: In this activity, the experimental hypothesis might be that the addition of an ...

pH Regulation in Cells

pH plays a critical role in maintaining normal cellular activities. It helps maintain the structure and function of various proteins, dictates the charge ...

Chemistry of the Cell

Overview of Functional Groups

Functional groups are a group of atoms with characteristic properties, which when linked to the carbon skeleton of a molecule, alter the properties of ...

Introduction to Carbohydrates

Carbohydrates, proteins, and fats are the primary macronutrients in the human diet. However, carbohydrates are the most favored source of energy in the ...

Carbohydrate Metabolism

Sugars as Energy Storage Molecules

What are Lipids?

lipid-derived-compounds-in-the-human-body

Lipid-derived Compounds in the Human Body

Fats and lipids are crucial components in the human body. Some lipid-derived compounds, such as fat-soluble vitamins, eicosanoids, lipoproteins, and ...

Fats as Energy Storage Molecules

What are Proteins?

Protein Organization

Globular Proteins

In organisms, proteins are the most abundant macromolecules. They act as the building blocks of life and play various crucial roles in the body. Proteins ...

Fibrous Proteins

Fibrous proteins are either long and narrow proteins or assemble to form long and thin structures. They contain repetitive units and usually consist of ...

Protein Denaturation

The function of proteins depends on their native three-dimensional structure, which is dictated by the amino acid sequence of the specific protein. ...

Role of Proteins in the Human Body

Proteins are the building block of life. They are also&#160; the most abundant macromolecules with as many diverse roles in the body. They are part of ...

Nucleic Acids and Nucleotides

Nucleic acids are the most important macromolecules for the continuity of life. They carry the cell&#39;s genetic blueprint and have instructions for its ...

Nucleic Acid Structure

The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group ...

ATP Energy Storage and Release

ATP and Macromolecule Synthesis

Biological macromolecules are organic compounds, predominantly composed of carbon atoms. The carbon atoms are covalently bonded with hydrogen, oxygen, ...

Construct an explanation to illustrate relationships between structure and function of major macromolecules essential for life.

LS.Bio.1.1

Introduction to Enzymes

The use of enzymes by humans dates to 7000 BCE. Humans first used enzymes to ferment sugars and produce alcohol without knowing that this was an ...

Enzymes and Activation Energy

The activation energy (or free energy of activation), abbreviated as Ea, is the small amount of energy input necessary for all chemical reactions to ...

Introduction to Enzyme Kinetics

Enzyme kinetics studies the rates of biochemical reactions. Scientists monitor the reaction rates for a particular enzymatic reaction at various substrate ...

Turnover Number and Catalytic Efficiency

The turnover number of an enzyme is the maximum number of substrate molecules it can transform per unit time. Turnover numbers for most enzymes range from ...

Catalytically Perfect Enzymes

The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at ...

introduction-to-mechanisms-of-enzyme-catalysis

Introduction to Mechanisms of Enzyme Catalysis

For many years, scientists thought that enzyme-substrate binding took place in a simple &#34;lock-and-key&#34; fashion. This model stated that the enzyme ...

Ligand Binding and Linkage

Cooperative Allosteric Transitions

Ribozymes

Carry out investigations to illustrate how enzymes act as catalysts for biochemical reactions and how environmental factors affect enzyme activity.

LS.Bio.1.2

What are Cells?

Cells are the smallest and basic units of life, whether it is a single cell that forms the entire organism, e.g., in a bacterium or trillions of them, ...

Cell Size

Cell sizes vary widely among and within organisms. Bacterial cells range between 1-10 micrometers (&#x3BC;m)and are considerably smaller than most ...

Eukaryotic Compartmentalization

One of the distinguishing features of eukaryotic cells is that they contain membrane-bound organelles, such as the nucleus and mitochondria, that carry ...

Prokaryotic Cells

Prokaryotes are small unicellular organisms that include the domains&#x2014;Archaea and Bacteria. Bacteria include many common organisms, such as ...

Cytoplasm

The cytoplasm consists of organelles and a framework of protein scaffolds called the cytoskeleton suspended in an aqueous solution, the cytosol. The ...

The Nucleus

The nucleus is a membrane-bound organelle that acts as a control center in a eukaryotic cell. It contains chromosomal DNA, which controls gene expression ...

Endoplasmic Reticulum

Endoplasmic ReticulumThe endoplasmic reticulum (ER) is an extensive network of membranous sacs and tubules in eukaryotic cells, continuous with the outer ...

Ribosomes

Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that ...

Golgi Apparatus

As they leave the Endoplasmic Reticulum (ER), properly folded and assembled proteins are selectively packaged into vesicles. These vesicles are ...

Lysosomes

Lysosomes are membrane-enclosed spherical sacs derived from the Golgi apparatus. The most important function of the lysosome is degrading macromolecules ...

Peroxisomes

Peroxisomes and mitochondria are two important oxygen-utilizing organelles in eukaryotic cells. Mitochondria carry out cellular respiration&#x2014;the ...

Introduction to the Cytoskeleton

Overview of the Cytoskeleton
The cytoskeleton is a network of protein filaments present within the cell, having three distinct filaments ...

Introduction to Actin

Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle ...

Cell Structure

Background
Cells represent the most basic biological units of all organisms, whether it be simple, single-celled organisms like bacteria, or large, ...

overview-of-myosin-structure-and-function

Overview of Myosin Structure and Function

Myosins are a family of molecular motor proteins, first identified in the skeletal muscles, where they are responsible for muscle contraction. Along with ...

Visualizing Onion and Cheek Cells
ExpandImmediately before the experiment, wash and peel onion bulbs for the class.
Remove the entire brown outer skin and ...

Microtubules

Microtubules are the thickest cytoskeletal filaments with a diameter of 25 nm. In prokaryotic organisms, microtubules are commonly found in locomotory ...

The Structure of Intermediate Filaments

The intermediate filaments are one of three widely studied cytoskeletal filaments. They are so named as their diameter (10 nm) is in between that of ...

Types of Intermediate Filaments

The intermediate filaments are an essential component of the cytoskeleton. Presently six types of intermediate filament have been identified. Type I and ...

Gap Junctions

Multicellular organisms employ a variety of ways for cells to communicate with each other. Gap junctions are specialized proteins that form pores between ...

The Extracellular Matrix

In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, ...

Tissues

Cells with similar structure and function are grouped into tissues. A group of tissues with a specialized function is called an organ. There are four main ...

Plant Cell Wall

The plant cell wall gives plant cells shape, support, and protection. As a cell matures, its cell wall specializes according to the cell type. For ...

Use models to explain how the structure of organelles determines its function and supports overall cell processes.

LS.Bio.1.3

Analyze how the relationship between structure and function supports life processes within organisms.

Cell Organization in Prokaryotes and Eukaryotes

Description

Transcript

More videos by Standards