Essential Biology 6.4- Gas Exchange

What are the adaptations and advantages of these adaptations with alveoli?

- Spherical Shape of alveoli- which provides a large surface area respiratory gases to diffuse through. - Flattened single cell thickness of each alveolus- Prevents respiratory gases from having to diffuse through more cell layers. - Moist inner lining- allow for efficient diffusion. -Associated capillary bed nearby- respiratory gases do not have to diffuse far to reach single cell thick capillaries.

What are the main reasons for a ventilation system?

- To maintain the concentration gradients of oxygen and carbon dioxide in the alveoli. -The body needs oxygen to make ATP via cellular respiration. - Oxygen needs to diffuse from the alveoli into the blood. Carbon Dioxide needs to diffuse from the blood into the alveoli. - For oxygen to diffuse and Carbon to diffuse there must be a high oxygen concentration and a low carbon dioxide concentration in the alveoli. ***The reason for the ventilation system makes this possible by getting rid of carbon in the alveoli and bringing in oxygen.

How many and what membranes does oxygen need to pass through to get to the red blood cell?

1. into alveolar cell (1 membrane) 2. out of alveolar cell (1 membrane) 3. into capillary wall (1 membrane) 4. out of capillary wall (1 membrane) 5. into RBC (1 membrane) *** A total of 5 membranes

How thick are alveoli and what happens here?

alveoli are tiny air sacks only one cell thick. The exchange of oxygen and carbon takes place here.

Causes and consequences of lung cancer?

Causes: -Exposure to radiation -Air pollution -Previous lung disease -family history of lung cancer -past cancer treatment -Previous smoking related cancers -lowered immunity Consequences: -Being short of breath -Having a cough most of the time -Coughing up phlegm with blood -An ache in the chest -Loss of apetitie -Tiredness/ Fatigue -Losing weight

What are the main causes of Emphysema and consequences?

Causes: -Smoking -Long History of chest infections -Air pollution -Chemical fumes and dust Consequences: -Difficulty breathing -Cough -Loss of appetite -Weight Loss

Humans are land-born so how do gases diffuse?

Gases need moist surface to diffuse and which our lungs are moist membranes, allowing oxygen to diffuse into the blood and carbon dioxide to diffuse out.

What must happen for gas exchange to be efficient?

High concentration gradients must maintained in the alveoli.

Small organisms can exchange gases directly with their surroundings through diffusion. What do Large organisms do?

Land-based mammals and waterborne mammals, including humans, have evolved internal ventilation systems which allow for gas exchange with the blood. As well as, the ventilation shows how the blood can be a medium for this.

How does the ventilation system maintain such a large concentration gradient?

Maintains this between the alveoli and the blood. The constant flow past the alveoli brings blood with high amounts of carbon dioxide concentration and low oxygen concentration. Breathing out keeps the carbon dioxide concentration in the alveoli low so it diffuses out of the blood. Breathing in keeps the oxygen concentration in the alveoli high and so it diffuses into the blood.

Gas Exchange

The exchange (diffusion) of oxygen and carbon dioxide to and from the blood at the alveoli and the respiring tissues.

What is the Essential Idea of Gas Exchange?

The lungs are actively ventilated to ensure that gas exchange can occur passively.,

The membranes are very thin on the alveoli. Why does this help aid in gas exchange?

The membrane is thin on capillaries and alveoli and so the path of diffusion is short.

Why are the surfaces wet on the alveoli?

The surfaces are wet because this helps for gases to dissolve ad thus makes diffusion easier. The fluid on the sides of alveoli from prevent those sides from sticking together.

Why are alveoli adapted to gas exchange?

They increase the surface area for gas exchange. There are millions and each have their own network of capillaries. The rich blood supply maintains a high concentration gradient of oxygen and carbon.

The external and intercontinental muscles work together in what way?

They work together because they're antagonistically.

Cell Respiration

This is the production of ATP at the cellular level (mitochondria). Aerobic Respiration uses oxygen, where and anaerobic does not.

What are tumors?

Tumors are an abnormal growth of tissue that develops at any stage in of life in part of the body.

What are type 1 pneumocytes and type 2 pneumocytes?

Type 1: they're extremely thin alveolar cells that are adapted to carry out gas exchange. Type 2: secrete a solution containing surfactant that creates a moist surface inside the alveoli to prevent the sides of the alveolus adhering to each other by reducing surface tension.

a malignant tumor and it is named after the part of the body where the cancer (primary tumor) first develops. Lung Cancer is the leading cause of death from cancer in the U.S.

What is cancer?

Ventilation

movement of air into and out of the lungs in two stages: Inhalation and Exhalation. This is controlled by the diaphragm and rib cage.