Question

Part A

What is the meaning of senescence? Discuss some organ system that go through senescence.

Part B

Discuss a type of cancer you found interesting or you want to learn more about. Mention the cause, use med terms mentioned in the chapter, how does it form, ways to detect that cancer, treatment, and prognosis.

Answer 1

Definition of senescence

Senescence is a biological aging : the gradual deterioration of functional characteristics.

Senescence literally means "the process of growing old." It's defined as the period of gradual decline that follows the development phase in an organism's life. there is two types of senescence cellular and organismal senescence.

CELLULAR SENESCENCE: When cells lose the ability to divide because of DNA damage or a shortening of telomeres, they go through a transformation that results in decline or destruction.

ORGANISMAL SENESCENCE:While cellular senescence may be a good thing because cells are continually replacing themselves, your body will eventually go into a period of decline known as organismal senescence.

How it affect organs:

Connective tissue changes, becoming more stiff. This makes the organs, blood vessels, and airways more rigid. Cell membranes change, so many tissues have more trouble getting oxygen and nutrients, and removing carbon dioxide and other wastes.

Because of cell and tissue changes, your organs also change as you age. Aging organs slowly lose function. Most people do not notice this loss immediately, because you rarely need to use your organs to their fullest ability.

2. CANCER

Cancer is the abnormal growth of cells and tissue.

here I want to discuss the cancer of the lung. Lung cancer is a type of cancer that begins in the lungs. lungs are two spongy organs in the chest that take in oxygen when inhale and release carbon dioxide when exhale.

People who smoke have the greatest risk of lung cancer, though lung cancer can also occur in people who have never smoked. The risk of lung cancer increases with the length of time and number of cigarettes smoked.

signs and symptoms of lung cancer may include:

• A new cough that doesn't go away
• Coughing up blood, even a small amount
• Shortness of breath
• Chest pain
• Hoarseness
• Losing weight without trying
• Bone pain
• Headache

Complications:

shortness of breath, blood in cough, pain , pleural effusion, spread in other part of the body etc.

Prevention: prevention is always better than cure so for that stop or quit smoking is the best way.

diagnosis of lung cancer:

History taking and physical assessment :

The history and physical examination may reveal the presence of symptoms or signs that are suspicious for lung cancer. In addition to asking about symptoms and risk factors for cancer development such as smoking, doctors may detect signs of breathing difficulties, airway obstruction, or infections in the lungs. Cyanosis, a bluish color of the skin and the mucous membranes due to insufficient oxygen in the blood,

The chest X-ray is the most common first diagnostic step when any new symptoms of lung cancer are present.

CT (computerized tomography) scans may be performed on the chest, abdomen, and/or brain to examine for both metastatic and lung tumors.

Magnetic resonance imaging (MRI) scans may be appropriate when precise detail about a tumor's location is required.

Sputum cytology :the simplest method to establish the diagnosis is the examination of sputum under a microscope.

Bronchoscopy: Examination of the airways by bronchoscopy (visualizing the airways through a thin, fiberoptic probe inserted through the nose or mouth) may reveal areas of tumor that can be sampled (biopsied) for diagnosis by a pathologist.

TREATMENT AND PROGNOSIS

Treatment for lung cancer primarily involves surgical removal of the cancer, chemotherapy, or radiation therapy, as well as combinations of these treatments.

curative (removal or eradication of a cancer) or palliative (measures that are unable to cure a cancer but can reduce pain and suffering).

Radiation: Radiation therapy uses high-energy X-rays or other types of radiation to kill dividing cancer cells.

Chemotherapy refers to the administration of drugs that stop the growth of cancer cells by killing them or preventing them from dividing.

prognosis

SCLC has the most aggressive growth of all lung cancers, with a median survival time of only two to four months after diagnosis when untreated when NSCLC Radiation therapy can produce a cure in a small minority of patients with NSCLC and leads to relief of symptoms in most patients