HAPPY THANKSGIVING TO ALL MY USA FANS

We must not forget to give thanks to the Almighty, Supreme, and Infinite God, each day that we have the breath of life. If your heart beats 72 beats per minute automatically, if you can perform the basic functions of life, if you can see and hear, or even reason and think, you must be grateful to your maker and creator. As you eat your turkey and drink various drinks, take a moment to say a

PRAYER 

OF

THANKSGIVING 

TO 

THE ONE WHO CREATED YOU

 AND 

BROUGHT YOU INTO BEING.

HAPPY THANKSGIVING TO ALL MY FAITHFUL FANS 

AND 

FOLLOWERS IN THE USA!

LYMPHOID TISSUES

The lymphatic system is involved with the clearing of infectious agents from the body. It transports the lymph which is the clear fluid originating from the plasma (liquid portion of blood). 

Functions

• Lymph drains interstitial fluid
• Transports dietary lipids 
•  Facilitates immune responses.

The plasma filters out of the capillaries and drains into lymphatic vessels to become lymph. It also transports fat. The lymph flows in the lymphatic vessels, lymphatic tissue and red bone marrow. The content of lymph is the same as interstitial fluid (the fluid around tissue cells). The Lymph eventually drains into venous blood via the right atrium.

What are the primary lymphatic organs? 

These are the sites where the lymphoid cells (T-LYMPHOCYTES and B-LYMPHOCYTES) are produced. It includes:

• Bone marrow
• Thymus

What are secondary lymphatic organs?

Secondary lymphoid tissues are arranged as a series of filters that monitor the contents of the extra-cellular fluids (lymph, interstitial fluid and blood). Secondary lymphoid tissues are also where lymphocytes are activated.

These include: 

• lymph nodes: The lymph is filtered by lymph nodes. These are encapsulated lymphoid tissue. There are about 100-200 lymph nodes, which mostly occur in the neck, thorax, abdomen and pelvis. They contain B-lymphocytes (cells) and T-lymphocytes (cells), which mostly enter the nodes via the blood stream. It also contains macrophages. 
• Mucosa Associated Lymphoid Tissue (MALT): These are non-encapsulated lymphoid aggregations found close to moist epithelial surfaces such as the mucous membranes of the digestive, respiratory and reproductive systems. They respond to any bacteria or micro-organisms that do get through the epithelia. The activated B-cells in these areas can develop into plasma cells, which then produce antibodies. They filter tissue fluid.  This makes up 85% of lymphoid tissue in the mucosa. They are usually small (around 1 millimeter in diameter), with the exception of the tonsils, peyers patches and the appendix.
• Tonsils are large partially-encapsulated masses of lymphoid tissue, found in the walls of the pharynx and nasopharynx, and at the base of the tongue. 
• Peyer's patches are large masses of confluent lymphoid follicles, found in the walls of the ileum (small intestine).
•  Spleen: The blood is filtered by the spleen, an encapsulated lymphoid tissue. This is the body's largest lymphatic organ. 

Functions of the spleen: 

• It is important for antibody production
• Facilitates immune responses to blood borne antigens 
•  It eliminates worn-out blood cells and platelets.

DIVERSITY IN ACTION

VIDEO ANIMATION ON ACTION POTENTIAL

This is a video produced by one of my students as part of her class science project on action potential. Enjoy watching it!

SCIENCE TEST MODULE 1

ANSWERS TO SCIENCE MODULE 1

1.   If the hydrogen ion concentration of a solution is 1 x 10^-5. What is the pH of the solution?

A.    1

B.     10

C.     5

D.    2

2.   If the hydrogen ion concentration of a solution is 1 x 10^-3. What can you say about the solution?

A.     It is a weak acid

B.      It is a strong acid

C.      It is a weak base

D.     It is a strong base

3. A student placed a blue ink drop in a jar of water. After some time, the whole water turned blue.  

Which of the following processes occurred?

      A. Osmosis

      B. Simple Diffusion

      C. Active Diffusion

      D. Facilitated diffusion

4. Water enters the roots of plants by which of the following process?

     A. Osmosis

     B. Simple Diffusion

     C. Active Diffusion

     D. Facilitated diffusion

5. Oxygen from the atmosphere enters the blood from the lung by ____________________ .

    A. Osmosis

    B. Simple Diffusion

    C. Active Diffusion

    D. Facilitated diffusion

6. During the formation of sodium chloride (NaCl), sodium loses one electron from its outermost shell (valence shell) to chlorine. Which type of bond is formed between these two atoms?  

   A. Metallic bond

   B. Ionic bond

   C. Covalent bond

   D. hydrogen bond

7. When a red blood cell (RBC) is placed in a hypertonic solution, it will ____________________

   A. Increase in size

   B. Shrink

   C. Rupture

   D. Remain the same

8. How would cream crackers taste if it is chewed slowly?

    A. Sweet    

    B. Bitter    

    C. Sour      

    D. Tasteless

9. What will be the end-product of sucrose digestion?

    A. glucose    

    B. glucose and galactose  

    C. galactose and fructose    

    D. glucose and fructose

10. Which of the following will turn blue-black when tested with Lugol's solution?

    A. protein  

    B. starch    

    C. glucose    

    D. fructose