Spongy bone tissue does not contain osteons. Instead, it consists of trabeculae, which are lamellae that are arranged as rods or plates. Red bone marrow is found between the trabuculae. Blood vessels within this tissue deliver nutrients to osteocytes and remove waste.

Spongy bone is found mostly at the ends of bones and contains red marrow. Bone marrow is found in the center of most bones and has many blood vessels.

Unlike compact bone that is mostly solid, spongy bone is full of open sections called pores. If you were to look at it in under a microscope, it would look a lot like your kitchen sponge. Pores are filled with marrow, nerves, and blood vessels that carry cells and nutrients in and out of the bone.

Bone marrow is found in the center of most bones and has many blood vessels. There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets.

People also sometimes want to know how low can hemoglobin go before causing death. In general, a hemoglobin less than 6.5 gm/dL is considered life-threatening.

Bone marrow failure happens when the marrow doesn’t produce enough red cells, white cells or platelets, or the blood cells that are produced are damaged or defective. This means the body can not supply itself with the blood it needs. Aplastic anemia, MDS and PNH are bone marrow failure diseases.

Blood disorder symptoms depend on the part of the blood affected. Some common symptoms include fatigue, fever, infections, and abnormal bleeding. Blood disorder treatment can sometimes cure the condition or at least manage it to prevent complications, but some disorders have a poor prognosis.

A number of diseases and conditions may affect white blood cell levels: Weak immune system. This is often caused by illnesses such as HIV/AIDS or by cancer treatment. Cancer treatments such as chemotherapy or radiation therapy can destroy white blood cells and leave you at risk for infection.

This results in a low number of RBCs. It is called “pernicious,” meaning dangerous, because it used to be untreatable and often fatal. Now, B-12 injections usually cure this type of anemia. Aplastic anemia: Aplastic anemia is a rare but serious condition in which your bone marrow stops making enough new blood cells.

Myelodysplastic syndrome (myelodysplasia) is a rare group of blood disorders that occur as a result of improper development of blood cells within the bone marrow. The three main types of blood cells (i.e., red blood cells, white blood cells and platelets) are affected.

Three bloodborne pathogens in particular, all viruses, are cited as of primary concern to health workers by the CDC-NIOSH: HIV, hepatitis B (HVB), & hepatitis C (HVC).

Hereditary spherocytosis (HS) is an inherited blood disease that results in anemia. If your child has HS, either parent may also have the disease; however, in about 25% of cases, neither parent of an affected child has the disease.

Myelodysplastic syndrome refers to a group of related disorders in which abnormal blood-forming cells develop in the bone marrow. At first, these cells interfere with the production of normal blood cells. Later, these cells may become cancerous, turning into a form of leukemia (see also Overview of Leukemia).

Your doctor will conduct a complete blood count (CBC) to determine if you have leukemia. This test may reveal if you have leukemic cells. Abnormal levels of white blood cells and abnormally low red blood cell or platelet counts can also indicate leukemia.

Common leukemia signs and symptoms include:

1. Fever or chills.
2. Persistent fatigue, weakness.
3. Frequent or severe infections.
4. Losing weight without trying.
5. Swollen lymph nodes, enlarged liver or spleen.
6. Easy bleeding or bruising.
7. Recurrent nosebleeds.
8. Tiny red spots in your skin (petechiae)