TOPIC 1.2 – CELL ULTRASTRUCTURES

1.2 – A - Prokaryotes

INTR

OIB BIO – 1.2 Cells can be divided into categories based on their structures and

complexity. The categories discussed in this topic are:

• Prokaryotes• Eukaryotes

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http://1.bp.blogspot.com/-SQ-NHcshRWg/VDgBuINdfnI/AAAAAAAAAJM/syK3PD8d66o/s1600/pro%2Band%2Beuk%2Bcells.png

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Key Terms

IB BIO – 1.2 Prokaryotes are cells whose genetic material is not contained within a nucleus and who have a simple structure.

They were the first life forms and do not have compartmentalized organelles.

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https://img.washingtonpost.com/rf/image_1484w/2010-2019/WashingtonPost/2011/06/10/Foreign/

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Applications

A2: Prokaryotes divide by binary fission.

Key Terms

Binary Fission

IB BIO – 1.2 Unlike eukaryotes, prokaryotes divide through a process called binary fission.

It is a type of asexual reproduction where the cell duplicates its genetic material before splitting its DNA and cytoplasm in half. The daughter cells are identical.

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https://upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Binary_fission.svg/1000px-Binary_fission.svg.png

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Applications

A2: Prokaryotes divide by binary fission.

Key Terms

Cell MembraneCytoplasmCell Wall

IB BIO – 1.2 7

https://micro.magnet.fsu.edu/cells/procaryotes/images/procaryote.jpg

Prokaryotic Structures• Cell membrane - surrounds the cell and controls what travels in

and out. It separates the cell from the environment.

• Cytoplasm - the liquid contents within the cell membrane. It is the site of metabolic reactions.

• Cell wall - located outside of the membrane. It provides structural support to the cells.

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Applications

A2: Prokaryotes divide by binary fission.

Key Terms

Ribosomes

Nucleoid

IB BIO – 1.2 8

http://media1.shmoop.com/images/biology/biobook_cells_12.png

Prokaryotic Structures• Ribosomes – site of protein synthesis

• Nucleoid – region containing the naked DNA. This means it is not associated with any proteins.

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Applications

A2: Prokaryotes divide by binary fission.

Key Terms

Cilia

Flagella

IB BIO – 1.2 9

http://www.microbiologyinfo.com/wp-content/uploads/2015/05/Differences-Between-Cilia-and-Flagella.jpg

Prokaryotic Structures

• Cilia – hair-like structures that assist in mobility as well as moving extracellular materials

• Flagella – long whip-like structures that is used as a ‘motor’ for movement

Understandings

U3: Electron microscopes have a much higher resolution than light microscopes.

Key Terms

Electron Microscope

IB BIO – 1.2 Because prokaryotic cells are so small, light microscopes cannot be used to observe them.

Electron microscopes use electron beams to visualize small samples and so have a much higher resolution.

They can produce images like those to the left, which can be used to study prokaryotic structures

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http://www.nature.com/ng/journal/v44/n2/images/ng.1056-F5.jpg

1.2 – B – Eukaryotes

INTR

OIB BIO – 1.2 Prokaryotes are simple organisms and were the original life forms

on Earth. Over time, they eukaryotes evolved from them.12

https://upload.wikimedia.org/wikipedia/commons/e/e6/Simplified_tree.pnghttps://upload.wikimedia.org/wikipedia/commons/e/e6/Simplified_tree.png

Understandings

U2: Eukaryotes have a compartmentalized cell structure.

Key Terms

Eukaryotes

IB BIO – 1.2 Eukaryotes are organisms that are complex and that have compartmentalized structures called organelles. Most notably, their DNA is contained within a nucleus. Eukaryotic organelles include…

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https://www.thinglink.com/scene/492442507804672000

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

Nucleus

Cell Membrane

IB BIO – 1.2The nucleus contains the cells genetic information in the form of chromosomes. It is surrounded by a double membrane and is the site of DNA replication and transcription.

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https://upload.wikimedia.org/wikipedia/commons/0/06/Blausen_0212_CellNucleus.png

The cell membrane is a phospholipid bilayer that surrounds the cell. It controls what diffuses in/out and contains embeddd proteins that serve many functions.

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

Ribosomes

Rough Endoplasmic

Reticulum

IB BIO – 1.2 Ribosomes are the site of protein synthesis.

The rough endoplasmic reticulum has ribosomeson its outer surface. Its role is to packageproteins for secretion. It sendsthem in vesicles to theGolgi apparatus.

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http://www.ncbi.nlm.nih.gov/projects/pmh/PMH_Authoring/media/Images/originals/NHGRI-85236.jpg

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

Vesicles

Golgi Apparatus

IB BIO – 1.2 Vesicles are small sacs made of membrane that are used to transport materials within the cell.

The Golgi apparatus processes proteins that are received from the rough ER. Then it sends them in vesicles to the cell membrane.

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https://media1.britannica.com/eb-media/52/116252-120-E654E669.jpg

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

IB BIO – 1.2 Together, the rough ER, Golgi apparatus and vesicles play a key role in moving materials in/out of the cell through the cell membrane.

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http://www.mun.ca/biology/desmid/brian/BIOL2060/BIOL2060-12/12_08.jpg

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

Mitochondrion

Chloroplast

IB BIO – 1.2 The mitochondrion is responsible for producing energy in the form of ATP. It does so through cell respiration.

Often called the ‘power house’ of the cell.

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http://www.astavitatest.com/wp-content/uploads/2016/02/micro1.jpg

The chloroplast is responsible for photosynthesis, which converts light energy into chemical energy.

It is only found in autotrophic organisms, which includes plantcells.

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

Microtubules

Centrioles

IB BIO – 1.2 Microtubules are fibers that play an important role in moving chromsomes during cell division.

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https://upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Centriole-en.svg/

In animal cells, microtubules are anchored at structurs called centrioles.

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

Vacuole

IB BIO – 1.2 Vacuoles are similar to vesicles in they are made of phospholipid bilayers. Their role is to store water and can be quite large in plants, which provides structural support.

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http://elte.prompt.hu/sites/default/files/tananyagok/StructureOfPlantsAndFungi/images/m6deddcd1.jpg

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

Cell Wall

IB BIO – 1.2 The cell wall is a rigid structure that is found outside the cell membrane in plant cells. Just like in prokaryotes, it provides structural support.

In plants, large vacuoles push against the cell wall which creates internal pressure. This allows plants to stand upright.

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https://upload.wikimedia.org/wikipedia/commons/7/7c/Eukaryota_cell_strucutre.PNG

Applications

A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.

Key Terms

IB BIO – 1.2 22

https://i.ytimg.com/vi/-zafJKbMPA8/maxresdefault.jpg

The primary differences between animal and plant cells are:• Plant cells contain chlorosplasts• Plant cells have large vacuoles• Plant cells have cell walls

REVI

EWIB BIO – 1.2 Identify the name and function of the following organelles 23

https://upload.wikimedia.org/wikipedia/commons/thumb/1/11/Animal_Cell.svg/2000px-Animal_Cell.svg.png

2 3 5 6 910 11 13 14

REVI

EWIB BIO – 1.2 Identify the organelles in the plant cell below 24

http://pulpbits.net/wp-content/uploads/2013/11/Unlabeled-Plant-Cell-pic-1-1024x1024.jpg

• Mitochondria• Vacuole• Cell wall• Cell membrane• Chloroplast• Nucleus• Rough ER• Ribosomes

1.2 – C – Micrographs & Drawings

Skills

S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.

Key Terms

IB BIO – 1.2 26Electron micrographs are images obtained using an electron microscope. These can be used to observe internal structures.

http://www4.uwsp.edu/biology/courses/botlab/images/Lab03Cells/03C-b%20-%20full.jpg

Skills

S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.

Key Terms

IB BIO – 1.2 27

?

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Structures:

Mitochondria

Lysosome

Eukaryote structures micrographIdentify the following structures in the micrograph

Skills

S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.

Key Terms

IB BIO – 1.2 28

Structures:

rER

Nucleus

Mitochondria

Lysosome

Golgi Apparatus

Free Ribosomes

Epithelium Cell MicrographIdentify the following structures in the micrograph

Skills

S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.

Key Terms

IB BIO – 1.2 29

Structures

ER

Nucleus

Nuclear membrane

Eukaryotes structures micrographIdentify the following structures in the micrograph

Skills

S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.

Key Terms

IB BIO – 1.2 30

Structures:

Vacuole

Chloroplast

Cell Wall

Eukaryote structures micrographIdentify the following structures in the micrograph

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Key Terms

IB BIO – 1.2 31

Structures:

Flagella

Cilia

Cell Wall

E. coli structures micrographIdentify the following structures in the micrograph

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Key Terms

IB BIO – 1.2 32

Structures:

Nucleoid

Cytoplasm

Cell Wall

E. coli structures micrographIdentify the following structures in the micrograph

Understandings

U1: Prokaryotes have a simple cell structure without compartmentalization.

Key Terms

IB BIO – 1.2 33

Structures:

Cytoplasm

Plasma membrane

Cell Wall

Nucleoid

E. coli structures micrographIdentify the following structures in the micrograph

Skills

S2: Drawing of the ultrastructure of eukaryotic cells based on electron micrographs.

Guidance

G2: Drawings of should show a membrane enclosing cytoplasm that contains ribosomes and membrane-bound organelles

IB BIO – 1.2 Animal Cell Diagram 34

Rough ER Cell Membrane NucleusRibosomes Golgi Apparatus Mitochondrion

Skills

S2: Drawing of the ultrastructure of eukaryotic cells based on electron micrographs.

Guidance

G2: Drawings of should show a membrane enclosing cytoplasm that contains ribosomes and membrane-bound organelles

IB BIO – 1.2 Plant Cell Diagram 35

http://garden.org/onlinecourse/Diagrams/c2/c2-1cell.gif

Rough ER Cell Membrane NucleusRibosomes Golgi Apparatus MitochondrionCell Wall Vacuole Chloroplast

Skills

S1: Drawing of the structure of prokaryotic cells based on micrographs.

Guidance

G1: Drawings of prokaryotic cells should show the cell wall, pili and flagella, and membrane enclosing cytoplasm that contains ribosomes and a nucleoid with naked DNA.

IB BIO – 1.2 36

http://image.wikifoundry.com/image/3/ySTgfE8BZEXCnVWQ0mdFaw253611/GW558H457

Prokaryote Diagram

Cell Wall Plasma Membrane CiliaFlagella 70S Ribosomes Nucleoid

REVI

EWIB BIO – 1.2 1. Compare prokaryotes and eukaryotes.

2. Compare the structure of plant and animal cells.

3. Outline the functions of the following organelles:- Nucleus - Cell Membrane- Mitochondria - Chloroplast- Cell Wall - Vacuole- Flagella - Cilia- Vesicle - Rough ER- Golgi Apparatus - Nucleoid

4. Draw and annotate diagrams of:- Prokaryotic Cell- Animal Cell- Plant Cell

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