Animal Digestive Systems

Flashcards about animal digestive systems covering topics like nutrition, digestion, and absorption.

What are the two main types of breakdown that occur in animal digestive systems?

Mechanical and chemical breakdown

What are heterotrophs?

Organisms that must feed on other organisms

What do herbivores eat?

Mainly feed on plants

What do carnivores eat?

Eat mainly animals

What do omnivores eat?

Ingest both plants and animals

What are the four main types of teeth?

Incisors, canines, premolars, and molars

What is dentition?

Arrangement of the teeth

What is the alimentary canal?

Hollow tube (~20 feet)

What three needs must an adequate diet satisfy?

Chemical energy for cellular processes, organic building blocks for macromolecules, and essential nutrients

What are the four macronutrients?

Carbohydrates, proteins, fats, and water

What are the two micronutrients?

Vitamins and minerals

What are nutrients?

Substances that allow the body to make energy, build and maintain tissues, and regulate bodily processes

Give some examples of energy-rich foods.

Whole grain cereals, millets, vegetable oils, ghee, butter, nuts, and oilseeds

Give some examples of body-building foods.

Pulses, nuts, oilseeds, milk and milk products, meat, fish, and poultry

Give some examples of protective foods.

Green leafy vegetables, other vegetables and fruits, eggs, milk and milk products, and flesh foods

What are essential nutrients?

Substances that an animal requires, but cannot be assembled from simple organic molecules

What are the four classes of essential nutrients?

Essential amino acids, essential fatty acids, vitamins, and minerals

What foods provide all the essential amino acids and are thus 'complete' proteins?

Meat, eggs, and cheese

What are vitamins?

Organic molecules required in the diet in very small amounts

Into what two categories are vitamins grouped?

Fat-soluble and water-soluble

What is a role of Vitamin B?

Help the body obtain energy from food and are important for metabolism

What is a role of Vitamin C?

Assists the body in the growth and healing of body tissues, improves the immune system

What is a role of Vitamin D?

Helps bone health through promoting absorption of calcium and phosphorous and helps immunity

What is a role of Vitamin A?

Helps maintain vision and immune system

What are minerals?

Simple inorganic nutrients, usually required in small amounts

What is a function of Calcium?

Bone and tooth formation, blood clotting, nerve and muscle function

What is a function of Iron?

Component of hemoglobin and of electron carriers

What is a function of Potassium?

Acid-base balance, water balance, nerve function

What is a function of Myoglobin?

Transport and storage of oxygen

What four main processes are involved in food processing?

Ingestion, digestion, absorption, and elimination

What is ingestion?

The act of eating or feeding

What are the four main feeding mechanisms of animals?

Filter feeding, substrate feeding, fluid feeding, and bulk feeding

What is digestion?

Breaking food down into molecules small enough to absorb

What is absorption?

Uptake of small molecules by body cells

What is elimination?

Passage of undigested material out of the digestive system

Into what smaller molecules do proteins break down during digestion?

Proteins break down into amino acids

Into what smaller molecules do starches break down during digestion?

Starches break down into monosaccharides

Into what smaller molecules do lipids break down during digestion?

Lipids break down into glycerol and fatty acids

Why are digestive compartments important?

Reduce the risk of an animal digesting its own cells and tissues

What are the mammalian accessory glands?

Salivary glands, the pancreas, the liver, and the gallbladder

What makes up the human digestive system?

A digestive tube, the alimentary canal, and accessory organs that secrete digestive chemicals

What are the functions of the mouth, or oral cavity?

Ingestion and the preliminary steps of digestion

What two types of digestion occur in the mouth?

Mechanical (teeth tear and grind food) and chemical (amylase/lipase in saliva breaks down starch)

What is the function of the pharynx?

Connects the mouth to the esophagus

What is the esophagus?

A muscular tube that connects the pharynx to the stomach

What is peristalsis?

Rhythmic waves of muscular contractions

What is the function of the stomach?

Stores food, chemical digestion, churns food into acid chyme

What is gastric juice comprised of?

Gastric juice has mucus, enzymes, and acid

What protects the stomach lining?

Pepsin is secreted in the inactive form of pepsinogen, mucus, gastric juice is not secreted constantly, and mitosis

What makes up gastric juice?

Hydrochloric acid (HCl) and pepsin

What do parietal cells secrete:

Secrete hydrogen and chloride ions separately into the lumen of the stomach

What do chief cells secrete:

Secrete inactive pepsinogen, which is activated to pepsin when mixed with hydrochloric acid in the stomach

How is Pepsinogen activated?

Pepsin activates more pepsinogen, starting a chain reaction

What is the small intestine?

The longest part of the alimentary canal, the major organ for chemical digestion and absorption

What is the function of the duodenum?

Receives digestive agents from several organs

What is the function of the pancreas?

Secretes juice that neutralizes stomach acids into the duodenum

What is the function of the liver?

Secretes bile, which is stored in the gallbladder, and helps digest fats

What proteases does the pancreas produce?

Trypsin and chymotrypsin

What do bile salts do?

Facilitate digestion of fats and are a major component of bile

What parts of the small intestine are specialized for absorption?

The jejunum and ileum

What do the Villi and microvilli provide?

A large surface area for absorption

What does the hepatic portal vein do?

Carries nutrient-rich blood from the capillaries of the villi to the liver, then to the heart

What is the function of bile salts in the digestion of fats?

Bile salts break up fat globules, increasing triglyceride exposure to hydrolysis.

Describe the function of lipase.

The enzyme lipase breaks triglycerides down to fatty acids and monoglycerides

After the enzyme lipase, what happens?

Monoglycerides and fatty acids diffuse into epithelial cells and are re-formed into triglycerides

What are Triglycerides incorporated into?

Triglycerides are incorporated into water-soluble particles called chylomicrons

What do chylomicrons enter?

Chylomicrons enter lacteals and are carried away by lymph

What is the fat absorption process?

Emulsification by bile salts, breakdown by lipase, diffusion into epithelial cells, reformation of triglycerides, packaging into chylomicrons, and transport via lacteals

What do epithelial cells do?

Absorb fatty acids and monoglycerides and recombine them into triglycerides

With what are fats coated?

Phospholipids, cholesterol, and proteins

What is a lacteal?

A lymphatic vessel in each villus

What does the Colon do?

Absorbs water from the alimentary canal and produces feces

What does the rectum do?

Store feces until it can be eliminated

What does the anus do?

Regulates opening of rectum and expels feces

What kind of relationship do humans have with many bacteria?

Mutualistic symbiosis

What role do some intestinal bacteria play?

Produce vitamins and regulate the development of the intestinal epithelium and the function of the innate immune system

What is the microbiome?

The collection of the microorganisms living in and on the body

What do scientists use to study the microbiome?

A DNA sequencing approach based on the polymerase chain reaction

Give four examples of bacterial phyla

Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria

Which macromolecule is broken down into Amino Acids?

Proteins

Chewing and grinding is an example of?

mechanical digestion

What organs are considered the mammalian accessory glands?

salivary galnds, liver, galbaldder , pancreas

What are the two types of digestion in oral cavity?

mechanical digestion and chemical digestion

What the function of the pharynx?

connects the mouth to the esophagus.

What is the Human Digestion System composed of ???

A digestive tube, the alimentary canal

Gastric juice is made up of?

hydrochloric acid (HCl) and pepsin

Gastric juice production involves ???

pepsinogen hcl dynamics

Digestion and Absorption Overview occurs in the?

Small Intestine

Contributing organs to digestion in small intestine are ?

The pancreas and liver

Based on functions ,what are the categorizations foods?

Energy Rich, Body Building, and Protective

What 3 needs must be satisfied with an adequate diet?

Chemical energy for cellular processes, macromolecules, and nutrients.

Bile is stored in the ?

the liver and gallbladder

the jejunum and ileum Is parts of the small intestine specialized for ?

absorption

What type of breakdown are in animal Digestive system

mechanical and chemical

Anorexia and Bulimia are types of?

Eating Disorders?

Weight gain and Weight loss is caused by?

Energy balance

Protein food in prefabricated form?

Essential Amino Acids

Which organic molecules is required in the diet in very small amounts?

Essential amino acids

What the two categories of vitamins?

Fat soluble and water soluble

Inorganic nutrients usually required in small amount is ?

Minerals