Chapter 14: The Respiratory System

Respiration

A catabolic process of breaking down of glucose to release energy for carrying out life processes.

Cellular Respiration

The process of energy release occurring inside living cells, also known as tissue respiration.

Glucose Breakdown

The chemical reaction where glucose (C6H12O6) is broken down into carbon dioxide (CO2), water (H2O), and energy (ATP).

ATP

a chemical substance that stores and provides energy for cellular activities. It is also known as the energy currency of the cell.

Energy Needs

Body cells require energy for various activities, including protein synthesis, muscle contraction, and cell division.

Aerobic Respiration

A type of respiration that requires oxygen, typically occurring in animals.

Anaerobic Respiration

A type of respiration that occurs in the absence of oxygen, producing lactic acid in animals.

Lactic Acid

A byproduct of anaerobic respiration in muscles, leading to fatigue and oxygen debt.

Glycolysis

The initial breakdown of glucose occurring in the cytoplasm, which does not require oxygen.

Krebs Cycle

The aerobic process occurring in mitochondria that further breaks down pyruvic acid to produce ATP and CO2.

Respiratory Organs

Structures involved in breathing, including the nose, pharynx, larynx, trachea, bronchi, and lungs.

Breathing

The physical process in which the atmospheric air is inhaled and forced out of the lungs.

Tidal Volume

The amount of air breathed in and out during normal quiet breathing, approximately 500 mL.

Vital Capacity

The volume of air that can be taken in and outby maximum inhalation and expiration ,approximately 4500 mL.

Hypoxia

A condition characterized by a deficiency of oxygen reaching the tissues.

Asphyxiation

A condition in which the blood becomes more venous by accumulation of more carbon dioxide and the oxygen supply is diminished

Respiratory Cycle

The sequence of inhalation and exhalation, including inspiration, expiration, and pauses.

Where is the Respiratory Centre located? And what is it affected by?

It is located in the Medulla Oblongata , and influenced by the CO2 content in the blood.

Alveoli

Tiny air sacs in the lungs where gas exchange occurs.

Differences in Anaerobic Respiration

In plants, anaerobic respiration produces ethanol and CO2, while in animals, it produces lactic acid.

Inspiratory reserve Volume(Complemental air)

Air that can be drawn in forcibly over and above the tidal air. 3000 mL

Inspiratory capacity

Total volume of air a person can breathe in after a normal Expiration. 3500 mL

Expiratory Reserve Volume (Supplemental Air)

Air that can be forcibly expelled out after normal expiration . 1000 mL

Residual Volume

Some air is always left in the lungs even after forcibly breathing out. This is the leftover air. 1500mL

Total Lung Capacity

Maximum air which can at any time be held in the two lungs. 6000 mL

Dead air Space

1.       Some tidal air is left in respiratory passages such as trachea and bronchi where no diffusion of gases can occur = 150 mL

Alveolar air

The tidal air contained in air sacs = 350 mL

Full Form of ATP

Adenosine triphosphate.

Cause for Hypoxia

Lack of Oxygen reaching tissues

Location of Respiratory Centre

In the medulla oblongata of brain.

What is Respiratory Centre stimulated by?

It is stimulated by the carbon dioxide content of the blood.

How does expired air differ from Inspired air?

• less oxygen

• more carbon dioxide

• more water vapour

• warmer

• may contain some bacteria

Effect of lack of Oxygen

• air sickness

• dizziness

• unsteady vision

• loss of hearing

• lack of muscular coordination

• Complete blackouts

Tissue or Internal Respiration

The process in which the cells of the body use the oxygen to oxidise the food and release energy . The carbon dioxide produced is sent out in expiration.

Location and function of diaphragm

• Diaphragm is located towards the base of the lungs.

• It contributes the enlargement of the chest cavity lengthwise .

Function of Intercostal Muscles

Helps in pulling the ribs outward and inward.

Membranes covering the lungs

Visceral Pleura and Parietal Pleura with Pleural fluid in between.

Function of Pleural fluid

The pleural fluid provides lubrication for free movement of the lungs by removing friction.

Function of C-shaped rings of cartilage

C-shaped rings of cartilage which provide flexibility and keep the trachea distended permananently.

Ways in which CO2 is transported to the lungs.

• As bicarbonates dissolved in plasma.

• in combination with haemoglobin of RBCs as carbamino-haemoglobin.

Functions of inner lining of nasal chambers

• Warms the air as it passes over.

• adds moisture to the air.

• mucous secretion entraps harmful particles.

What is oxygen debt?

The condition in which the accumulation of lactic acid gives the feeling of fatigue.

Why does shivering and teeth chlattering occur?

It is an emergency activity of the muscle cells to produce extra heat to keep the body warm(when feeling cold).