Animal Physiology Quiz

Ingestion

• The process of taking food into the body, beginning in the mouth.
• Mechanical digestion through teeth and tongue.
• Chemical breakdown by saliva, containing enzymes like amylase.
• Amylase breaks down starch into maltose.
• Saliva lubricates food, aiding swallowing.

Dental Formulas

• Incisors are used for biting.
• Canines are used for tearing.
• Premolars are used for grinding.
• Molars are used for crushing.

Monogastric Digestion

• Characterized by a single stomach, like humans and pigs.
• Amylase is secreted in the mouth to begin starch digestion.
• Food forms a bolus and is passed into the esophagus.
• Peristalsis, wave-like muscular contractions, moves food through the digestive tract.

Ruminant Digestion

• Occurs in animals like cattle and sheep, possessing a four-chamber stomach.
• Chambers: Rumen, Reticulum, Omasum, and Abomasum.
• Rumen is the first chamber, containing microorganisms that break down cellulose.
• Cellulose is the tough material found in grasses.
• Rumen has a pH of 7, with carbon dioxide and methane gas produced.
• Bloat can occur if gas buildup is trapped due to a pH drop below 5, often caused by white clover ingestion.
• Bloat is treated with antacids or an incision in the abdomen to release gas.

Symbiosis in Ruminants

• A relationship where both organisms benefit.
• Bacteria in the rumen digest cellulose, providing glucose and vitamins for the cow.
• The cow provides a habitat and nutrients for the bacteria.

Reticulum

• The second chamber, responsible for regurgitating partially digested food (cud) back to the mouth for further chewing.

Omasum

• The third chamber, where water and liquid are reabsorbed from the food.

Abomasum

• The fourth chamber, often referred to as the true stomach.
• Responsible for breaking down proteins and completing the digestion process.

Small Intestine

• Composed of the duodenum and ileum.
• Peristalsis continues to move food through.
• The duodenum connects the stomach to the ileum.
• The ileum is where most nutrient absorption takes place.
• Bile and pancreatic juices are secreted into the small intestine to aid digestion.

Large Intestine

• Consists of the caecum and colon.
• Primarily responsible for water reabsorption and waste passage to the anus.

Young Ruminants

• Do not have a fully developed rumen at birth.
• Milk is directly transferred to the abomasum for digestion.
• As they mature, microorganisms develop in the rumen.
• The rumen and reticulum take around six weeks to fully develop.

Monogastric Animals

• Possess only one stomach, lacking a rumen.
• Unable to digest cellulose.

The Liver in Monogastric Animals

• A vital organ with multiple functions:
• Stores glucose as glycogen.
• Breaks down glycogen into glucose when energy levels are low.
• Stores vitamins and minerals.
• Detoxes harmful substances like ammonia, converting it to urea.
• Recycles red blood cells, using their pigments in bile production.
• Regulates temperature by producing heat and warming blood.

Chicken Digestion

• Chickens lack teeth, but have a beak adapted for specific feeding.
• Food passes from the esophagus to the stomach.
• Chickens swallow grit, which is stored in the gizzard to mechanically grind food.
• They also have a crop, which stores food for later consumption.
• The stomach is divided into the proventriculus and the gizzard.
• Chickens do not have a separate urinary tract, passing both urine and feces together.

Explore the intricate processes of ingestion, mechanical and chemical digestion, and the distinct roles of various teeth in breaking down food. This quiz covers both monogastric and ruminant digestion, highlighting the unique digestive systems of different species.