Bio

• Direct respiratory

  
  

  Many aquatic organisms obtain air directly from their

  environment.
• Indirect Respiration

  
  

  Ordinary respiration in different animals is formed by

  various respiratory organs or systems, such as the body

  covering, gills, lungs, or trachea. These structures are

  unlike in appearance but have fundamentally the same

  function; each comprises a moist permeable membrane

  through which molecules of oxygen and carbon dioxide

  diffuses readily.
• Gills

  
  

  The respiratory systems of multicellular aquatic animals.
• countercurrent flow

  where the blood and water meet in opposite directions.
• Lungs

  
  

  a chamber lined by moist epithelium underlaid by a network of blood capillaries, where atmospheric air can be used.
• alveoli


  Its wall are partitioned in varying degree to form compartments called
• cutaneous breathing

  they use their skin for gas exchange
• External respiration

  Is the exchange of gases between the atmosphere and the blood in the lungs
• internal respiration

  is gas exchange between the blood and the cells of the body.
• nasal septum

  Is a partition dividing the nasal cavity into right and left parts.
• Pharynx

  the common passageway of both food and air.
• Larynx

  It is also known as the voice box due to the presence of vocal cords which are the primary source of voice production.
• Trachea

  or windpipe,is a membranous tubethat consists ofconnective tissue andsmooth muscle,reinforced with 16-20 C-shaped pieces ofcartilage.
• alveolar ducts

  are like long, branching hallways with many open doorways.
• Hemoglobin

  
  

  a so-called respiratory pigment, formed by the union of heme, which contains iron, with a colorless protein globin.
• stomata


  They are considered the “breathing organs” of plants.
• lenticels

  These are porous structures which also function for gas exchange.
• Autotrophs

  such as plants and other photosynthetic organisms, convert water and carbon dioxide with the Sun’s energy, into organic sugars which they can use for growth and development

  
  

  Plants are the primary source of food for all living things.
• heterotrophs

  organisms that cannot make their own food.

  
  

  depend on the other organisms for their food which is why they are called the consumers in the ecosystem.
• digestion

  The basic stages of the digestive process include ingestion, digestion, absorption, and elimination.
• Bulk feeders

  which include most animals including humans, eat large pieces of food.
• mouth

  is the first chamber of man’s digestive tract It is where food is captured and manipulated by the teeth, tongue, and cheek muscles for physical digestion and lubricated with saliva for initial chemical digestion.
• teeth

  for mastication
• tongue

  for manipulation of food in mixing it with saliva, pushing food towards the teeth, and making food into a bolus, and for deglutition.
• cheek muscles

  for mastication.
• tongue

  is a large, muscular organ that occupies most of the oral cavity.
• frenulum

  There is an anterior attachment to the floor by means of a thin fold of tissue
• Saliva contains two

  
  

  enzymes, ptyalin and maltase.
• Ptyalin

  breaks starches into maltose
• maltase

  breaks down maltose to glucose.
• Esophagus

  a flexible tube carrying food past the region of the heart and lungs, toward the stomach.
• peristalsis

  Circular muscles surrounding it contract in sequence above the swallowed food mass, squeezing it down towards the stomach in aprocess.
• Stomach

  an expansible muscular sac capable of holding from 2 to 4 liters of food and liquids.
• pyloric sphincter

  Food is retained in the stomach by a ring of circular muscle
• Gastrin

  A hormone that stimulates secretion of hydrochloric acid by the parietal cells of the stomach.
• Pepsinogen

  an inactive form of protein-digesting enzyme that is secreted and released by the zymogenic cells of the stomach.
• Mucus

  A protective secretion of the stomach mucous cells to prevent the damaging effect of HCl.
• chyme

  Food in the stomach is gradually converted to a thick, acidic liquid.
• small intestine

  
  

  A long, slender , coiled tube, which is the principal region for chemical digestion and absorption.
• villi

  To facilitate absorption, the small intestine has an internal surface lined with finger like projections