molecular biology 1-5

Molecular Biology 1-5

put together by: Linda Fahlberg-Stojanovska

Disclaimer: I put these together for my kid for his smartphone.

However, I found most images had very small type and increased the font size. I am posting it because another teacher might find this useful.

The sources are given. If I have used anything illegally, write me and I will take it off.

• Tissues, Organs and Systems

• Connective Tissues

• Cell Adhesion

• Endocrine System + Hormones

• Circulatory System + Blood

Contents

Tissues, Organs and Systems1. A tissue is a cellular organizational level intermediate

between cells and a complete organism.

2. An organ is a collection of tissues joined in structural unit to serve a common function.

3. A biological system (or organ system or body system) is a group of organs that work together to perform a certain task

4. A group of systems composes an organism, e.g. the human body.

Systems of Human Body1. Circulatory system

2. Digestive system

3. Endocrine system

4. Integumentary (skin) system

5. Lymphatic system

6. Muscular system/ Skeletal system

7. Nervous system

8. Reproductive system

9. Respiratory system

10.Excretory System / Urinary system

Tissues - Animal• Tissue is a cellular organizational level intermediate between

cells and a complete organism.

• Four basic types of animal tissue– epithelial tissue

– connective tissue

– muscle tissue and

– nervous tissue

Epithelial Tissues

Epithelial tissues•one of four basic types of tissue

•line the cavities and surfaces of structures throughout the body,

•form many glands.

Functions of epithelial cells include

•secretion, selective absorption, protection, transcellular transport and detection of sensation.

Connective TissuesConnective tissues (CT)•one of four basic types of animal tissue

•most diverse tissue, found throughout body

CT has 3 main components

•cells,

•fibers, and

•ground substance (non-cellular material of extracellular matrix ECM)

Connective TissuesFunctions of connective tissues include •Storage of energy•Protection of organs•Provide structural framework for the body•Connection of body tissues.

Fibrous connective tissue proteins– Collagen– Elastin

– Recticular

Proteins of Connective Tissue - Collagen• Collagen is the main component of connective

tissue, and is the most abundant protein in mammals, making up about 25% to 35% of the whole-body protein content.

• Collagen is a fibrous matrix protein found in fibrous tissues such as tendon, ligament and skin, and is also abundant in cornea, cartilage, bone, blood vessels, the gut, and intervertebral disc.

• The fibroblast is the cell which creates collagen.

Proteins of Connective Tissue - Proteoglycin

• Proteoglycans are the major component of the ground substance (non-cellular parts of ECM).

• They form large complexes, both to other proteoglycans, to hyaluronan and to fibrous matrix proteins (such as collagen).

• They are also involved in binding cations (such as sodium, potassium and calcium) and water, and also regulating the movement of molecules through the matrix.

Proteins of Connective Tissue - ECM

Proteins of Connective Tissue - Elastin

• Elastin is a fibrous matrix protein of connective tissue.

• Elastin is elastic - it allows many tissues in the body to resume their shape after stretching or contracting.

• Elastin helps skin to return to its original position when it is poked or pinched.

• Elastin is also an important load-bearing tissue in the bodies of vertebrates and

• It used in places where mechanical energy is required to be stored.

Proteins of Connective Tissue - Elastin

Tissues - PlantThree basic types of plant tissue•epidermis, the ground tissue, and the vascular tissue.

•Epidermis – forms the outer surface of the leaves and of the young plant body.

•Ground tissue - manufactures and stores nutrients.

•Vascular tissue - The primary components are xylem and phloem - transport fluid and nutrients internally.

Cell Adhesion - Connectivity• Cell Adhesion is the binding of a cell

– to another cell, a surface, or to the extracellular matrix.

• Cell Adhesion uses molecules such as

– selectins,

– integrins, and

– cadherins

• Correct cellular adhesion is essential in maintaining multicellular structure. It can link the cytoplasm of cells and can be involved in signal transduction.

Cell Adhesion - Junctions• A cell junction - is cell-to-cell adhesion in animals

Plants have plasmodesmata.

In vertebrates, 3 major types of cell junctions:

• Tight junctions

• Adherens junctions and Desmosome junctions

(Anchoring Junctions)

• Gap junctions

(Communicating Junction)

Cell Connectivity - Junctions

Cell Connectivity - Cadherins• Cadherins ("calcium-dependent adhesion") are a

class of type-1 transmembrane proteins.

• They are dependent on calcium (Ca2+) ions to function

• The cadherin superfamily includes

– cadherins,

– protocadherins

– desmosomes …

Tight JunctionsA tight junction

is virtually impenetrable to

fluid.

http://en.wikipedia.org/wiki/Tight_junction

Adherens JunctionA adherens

junction is a “sticky” junction where the

transmembrane protein fibers adhere to each other in the extracellular matrix.

http://en.wikipedia.org/wiki/Adherens_junction

Desmosome Junction

• A desmosome junction is an anchoring junction.

• Desmosomes help to resist shearing forces.

• The intercellular space is very wide (about 30 nm).

• Desmosomes are found in epithelial and in muscle

tissue.

Desmosome Junction• Desmosomes are

molecular complexes of cell adhesion proteins and linking proteins that attach the cell surface adhesion proteins to intracellular keratin cytoskeletal filaments.

http://en.wikipedia.org/wiki/Desmosome

Gap JunctionA gap junction directly connects the cytoplasm

of two cells allowing various molecules and ions to pass between

cells.

Gap junctions are analogous to the

plasmodesmata that join plant cells.

http://en.wikipedia.org/wiki/Gap_junction

Cell–to–Cell Adhesion in Plants• Plasmodesma is a microscopic channel which goes between

the cell walls of plant cells enabling transport and communication between them.

• Plant cell is surrounded by a polysaccharide cell wall.

• Neighbouring plant cells are therefore separated by a pair of cell walls forming an extracellular domain divided by a lamella.

• The plasmodesmata connected t

Cell–to–Cell Adhesion in Plants

http://en.wikipedia.org/wiki/Plasmodesma

Cell–to–Cell Adhesion in Plants

Endocrine System

The endocrine system is the

system of glands, each of which

secretes a type of hormone directly

into the bloodstream to

regulate the body.(Exocrine system

uses ducts that open into the

environment.)

Hormones• Hormones are substances produced by glands and released into the

bloodstream. They affect activity in cells at other locations of the body. • The binding of a hormone to a receptor speeds up, slows down, or in

some other way alters the cell's function. • Hormones bind to receptors

– on a cell's surface (protein hormone) or – inside a cell (steroid hormone).

Hormones• Hormones are either proteins or steroids.• Hormones can also be classified by their chemical composition• Monoamine hormones - contain one amino group that is

connected to an aromatic ring by a two-carbon chain• Peptide hormones are protein hormones and are synthesized in

cells from amino acids according to an mRNA template, which is itself synthesized from a DNA.

• Lipid and phospholipid –derived hormones

– Mainly steroid hormones.

Monoamine Hormones• Monoamine hormones

– Histamine

– Catecholamines, e.g. Dopamine

– Adrenaline, e.g. Epinephrine

Monoamine HormonesTyrosine (amino acid)

Peptide Hormones• Peptide hormones consist of chains of amino acids.

– Vasopressin is a peptide hormone that controls the reabsorption of molecules in the tubules of the kidneys by affecting the tissue's permeability.

– Insulin is a peptide hormone, produced by the pancreas, which is central to regulating carbohydrate and fat metabolism in the body. Insulin causes cells in the liver, muscle, and fat tissue to take up glucose from the blood, storing it as glycogen in the liver and muscle.

Vasopressin is nonapeptid (9 amino acids):Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly

Peptide Hormones• Peptide hormones

• Steroids are lipids with a characteristic arrangement of four cycloalkane rings.

• Steroids can be hormones or sterols (ex: cholesterol)

• Examples of steroid hormones:

Lipid - Steroid Hormones

• Protein hormones bind with receptors on the surface of cells.

• Steroid hormones are small molecules that are fat-soluble (and thus easily diffuse through cell walls to bind with receptors inside of cells

Hormones

Protein hormones bind to receptors on surface of cells.

http://www.emcom.ca/faq/ans3.shtml

Protein Hormones

Protein hormones bind to receptors on surface of cells.

Protein Hormones

Steroid hormones bind to receptors inside cells.

Steroid Hormones

Circulatory System

The circulatory system is an organ system helps maintain homeostasis and fight disease bypassing•nutrients such as amino acids, electrolytes and lymph,

•gases such as O2 and CO2

•hormones and •blood cells, etc.

to and from cells in the body.

Blood Clotting Cascade

• Thrombin is the most important constituent of the coagulation cascade in terms of its feedback and activation roles

• Tissue factor pathway (extrinsic) – primary pathway– The main role of the tissue factor pathway is to generate a "thrombin

burst" in releasing thrombin instantaneously.

• Contact activation pathway (intrinsic) - secondary– formation of complex on collagen

• Common pathway – here thrombin performs its primary role which is to convert fibrinogen to fibrin, the building block of a hemostatic plug.

http://en.wikipedia.org/wiki/Coagulation


• Coagulation is the process by which blood forms clots.

• It is an important part of hemostasis, the stopping of blood loss from a damaged vessel.

• In coagulation, a damaged blood vessel wall is covered by a platelet and fibrin-containing clot to stop bleeding and begin repair of the damaged vessel.

• Disorders of coagulation can lead to an increased risk of bleeding (hemorrhage) or obstructive clotting (thrombosis).


http://en.wikipedia.org/wiki/Coagulation

Blood Cells

• leukocytes WBC (natural immune response)

• thrombocytes - platelets (blood clotting)

• erythrocytes RBC (oxygen transport)

http://shs-bio-6th-wood.wikispaces.com/Topic+16-Blood-+Erythrocytes,+Leukocytes,+Platelets,+%26+Plasma

Blood Separation

http://en.wikipedia.org/wiki/Buffy_coat

Blood Separation

• Three anticoagulants can be used to inhibit coagulation in donor blood

• EDTA– removes calcium from the blood, but does not distort blood

cells.

• Heparin– Stops the formation of thrombin from prothrombin therefore

stopping formation of fibrin from fibrinogen

• Na-Citrate – removes calcium from the blood, but not as effective as

EDTA and harder to regulate.

molecular biology 1-5

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