Digest and absorb nutrients Small intestine - Spada UNS

6. ANIMAL DIGESTION

1. The Concept Of Energy Distribution Involve Gross Energy, Indigestible

Energy, Metabolizable Energy,

Specific Dinamik Action, And Nett Energy

Nutrient Absorbtion

2. Nutrient Absorbtion

 To enter the body, nutrients accumulate in the

lumen when the digested food must pass through or penetrate the wall of the digestive tract.

 Limited amount of nutrients absorbed in the

stomach colon clan, but most absorption occurs in the small intestine.

 A very large surface microvilli is an adaptation that fits perfectly with the task of nutrient absorption.

3. Animals sense food using chemical, electrical, and

thermal cues

a. Animals sense food using chemical

Many animals possess means of detecting the presence of specific chemicals in the environment.

The chemical may be a nutrient, and movement toward the source of the nutrient increases the likelihood that the animal will find more food

For examples:

 Hymenolepis diminuta undergoes diurnal migrations up and down the GI tract of its host, following the nutrients released from the meal under digestion

 Earthworm, Entire body covered with chemoreceptors (taste receptors)

the chemical that is detected

rather a signal that prey is nearby

For example:

 When a Hydra detect small organic molecules such as proline or reduced glutathione, it waves its tentacles and opens its mouth

Complex animals use gustatory and olfactory receptor to locate food

Example for animals use it receptor are:

 Herbivorous insect, such as aphids, use gustatory receptor to detect chemicals that either stimulate feeding (phagostimulants) or deter feeding (phagodeterrents)

 Silkworm Moth can detect pheromones up to 11 km

B. Animals sense food using electrical

 Many animals find prey by sensing the energy emitted or reflected from the animal in the form of light, sound, and electricity

For examples:

• A bird of prey, such as the golden eagle, uses its visual system to spot a field mouse moving in a distant meadow

• Sea dog to hunt fish, even in turbid waters though. It turns out, seals use whiskers to detect traces left by their prey in water, up to half a minute

• Sharks, and some other fish are sensitive to the electric fields generated by other animals in the water. They use this information to track prey

c. Animals sense food using thermal cues

 Some insects can detect the infrared light emission emitted from warm bodies of potential prey species. Light can also be produced by animals in conjunction with foraging strategies

For example:

• Predatory firefly species attract a prey firefly species by producing a light pattern that mimics the mating signal of the prey

• Deep-sea fish use bioluminescent appendages to lure small prey

• Rattlesnakes and other pit vipers use their eyes to see during the day. But at night they use infrared sensor organs to detect and hunt warm-blooded prey

4. Symbiotic Organism Contribute

to Animal Digestive Physiology

• In digestive system, many animals benefit from the assistance of symbiotic organism that live outside the animal tissues

• Examples of symbiotic:

a. species of birds eat the wax found in beehives.

Bacteria within the bird gut break down he wax into shorter carbon units that can be absorbed by the animal

b. Marine animals that feed on plankton can digest the chitin exoskeleton with the help of symbiotic bacteria

c. Whales hold chitinolytic bacteria in gastric ceca

• Some termonology relate to symbionts that participate in digestion:

1. Enterosymbionts

2. Exosymbiont

3. Endosymbionts

Chemolithotrophic Symbionts

• The organism that live at the base of these alternative food webs are chemolithotrophic bacteria.

• Characteristics of chemolithotrophic bacteria:

a. produce energy by metabolizing inorganic molecules

b. two main types sewage outfalls and deep-sea vents.

c. As the sewage outfall, chemolithotrophic bacteria are the nutritional base of the ecosystem, providing food for many species of invertebrates.

Picture of chemolithotrophic bacteria

Symbiont in

Pogonophorans

 Some species of animals enter into symbiont relationship with chemolithotrophic bacteria.

 Several species appear to cultivate

chemolithotrophic bacteria on their body

surfaces. A few species, such as the giant clam , house chemolithotrophic bacteria within their bodies as endosymbionts

Pogonophorans characteristic

• As an adult, it lacks a mouth and GI tract. While it may absorb some nutrients across the epithelium, most of the nutrition comes as a result of an unusual symbiotic arrangement with chemolithotrophic bacteria.

• The bacteria are housed at very high concentration in an internal sac called a trophosome

• The worm ensures that the bacteria receive the

precursors for biosynthesis (CO₂ and H₂S), and then collects the biosynthetic products: sugar and amino acids.

5. ANIMAL DIGEST FOOD 1. Receiving

2. Distributing and storing 3. Digesting and absorbing nutrients

4. Absorbing water and

defecation

Mouth Cavity

 Digestion of food physically and chemically begins in the mouth.

 more than 1 liter of saliva are secreted in the mouth every day.

 The tongue will taste the food, manipulate during chewing, and help shape the food into a ball called a bolus.

pharinx

When ANIMAL swallow, the top of the windpipe will move upwards so that the hole opening, glottis, closed by a cover of cartilage, epiglottis.

Esophagus

Esophagus drains food from the pharynx down to the stomach. Peristalsis will

promote narrow bolus along the esophagus.

Stomach

Gastric provides

beginning of the digestion process, which often has an acid environment. In several vertebrate and

invertebrate, the stomach also continues to stir the food. Intestine further digestion process that

began in the stomach and absorbing food substance and water.

Small Intestine

 small intestine is part of the most long digestive tract.

 About 25 cm in the first of the small intestine called the duodenum.

 Secretion work of duodenal epithelium secretion obtained from liver and pancreas.

 Small intestine in some animals contain many bacteria, protozoa, and fungi.

Macromolecule digestion in small intestine

 Carbohydrate

Carbohidrate digestion is starch and glycogen, it’s begun by salivary amylase in the oral

cavity that continues in the small intestine.

 Protein

Protein digestion in the small intestine

involves the completion of work begun by pepsin in the stomach.

 Nucleid acid

 lipid

Macromolecule digestion in small intestine (2)

 Nucleid acid

Digestion of nucleic acids involved in

hydrolytic similar to those seen in proteins. A group of enzymes called nuclease hydrolyzes DNA and RNA in the food into its component nucleotides.

 Lipid

Almost all the fat in a meal reaches the small intestine in conditions not yet fully digested.

large intestine

.

Food is no longer

broken down at this stage of digestion.

It also compacts feces, and stores fecal matter in the rectum until it can be discharged via anus in defecation.

Cow With Fistula

animals can live

perfectly well with a permanent hole in their stomachs.

Scientists call these surgically made

holes, fistulas,

which are covered by a canulla

Simple Animals Digest Food Within Phagocytic Vesicles

The simplest of animals, the sponges, obtain nutriens primarily by phagocytosis, much like protists such as the amoeba.

Water carrying food particles passes through the sponge’s network of pores and channels, flowing in currents generated by flagellated cells called choanocytes.

Other metazoan possess

something a kin to a mouth an entrance to an internal

compartment that carries out

digestion. The challenge for many animals is to get the food to the mouth. Cnidarians, such as coral

and Hydra, use tentacles to capture small prey, such as zooplankton.

Once the prey is captured, the tentacle bends to the mouth to release the food.

The mouth gapes to permit food to enter the gastrovascular cavity.

Movement down the tentacles and into the mouth is aided by a layer of mucus secreted by the opithelial cells.

The wall of the gastrovascular cavity is

composed of

gastrodermal cells, including nutritive cells and enzymatic gland cells.

Feeding Structure are Matched to Diet

Most animals have some form of specialized mouthparts to assist in feeding. The mouth itself may be lined with hard structures that grasp or cut the food.

Digestive Systems

The evolutionary history of digestive systems is marked by increasing

anatomical and functional

specialization.

Ancient

invertebrates possess simple

digestive sacs that food enters and

leaves through a single opening to form a two-way gut.

How Animals Obtained Food

depending on the composition of which is owned equipment and its ability to PREPARE food to be absorbed.

Primitive animals that do not yet have specific food digestion equipment, such as protozoa, parasites, and tapeworms, require food in the form of dissolved organic substances.

The animals are taking food through absorption or pinositosis.

Equipment owned food digestion is usually a food vacuole.

Animals that live stick on like hydra and coelenterata get food by way of trapping (trapping method). Important tool to support that method is cnidoblast or nematocyte, which are usually equipped with venom to capture prey.

Digestive Process in Protozoans

•Euglena

All euglena have

chloroplasts and can make their own food by photosynthesis.

They are not completely

autotrophic though, euglena can also absorb food from their

environment. Euglena usually live in quiet ponds or puddles.

•Amoeba By pushing the endoplasm toward the cell membrane, the amoeba causes its body to extend and creep along.

The amoeba also uses this method to consume its food. The pseudopodia extend out and wrap around a food particle in a process call phagocytosis.

The food is then engulfed into the amoeba and digested by the enzymes contained in the amoeba's lysosomes.

As the food is digested it exists in a structure called a food vacuole.

•Paramecia

Because paramecia live in water, they require an organelle to pump out excess water so they do not lyse (burst). These organelles are the contractile vacuoles, usually one at each end, each surrounded by several radiating canals which collect water from the surrounding cytoplasm. The contractile vacuoles serve a critical function of osmoregulation, as water tends to accumulate inside the cytoplasm due to

osmotic pressure.

6. GI TRACT

In general, the digestive tract has 4 main parts and have function, there are :

Ingestion

Digestion (distribute and store) Digest and absorb nutrients

Absorb water and defecation

(elimination

⁾

Ingestion



A. mouth

• B. Pharyngeal

• C. Esophagus

A. mouth

• Digestion of food

physically and chemically begins in the mouth

• During mastication, teeth with various forms will be cut, crush and grind the food, which makes the

food easier to swallow and increase the surface area.

• salivary glands release saliva through the duct or channel to the oral cavity

• Example mouth variation in bird

BACK

B. Pharyngeal



Area we call the esophagus is faring, the intersection that led to the

esophagus and trachea (windpipe).



When we swallow, the top of the

windpipe will move upwards so that the hole opening, glottis, closed by a cover of cartilage, the epiglottis

BACK

C. Esophagus

• Esophageal drain food from the pharynx down to the stomach.

• Peristalsis will promote narrow bolus along the esophagus.

BACK

Digestion (distribute and store)

in stomach

 Gastric provide process - beginning the process of digestion, which often has an acid environment.

 . In several vertebrate and invertebrate, the stomach also continues to stir the food.

stomach

• The general plan of GI tract similar among vertebrate, but taxa differ in the type of compartments. The vertebrate gut differs widely in complexity and length among

species. Each group of vertebrates is drawn to the same body length to emphasize the

differences length.

Types of phylorus

• A. Monogastrik

• B. Digastrik

• C. Poligastrik

A. Monogastrik

 Digestion of food is mechanically carried out in various ways.

 Monogastric stomach is a single bag of strong muscles, typical of vertebrate carnivores or Omnivore.

BACK

B. Digastrik

 Some birds and insects have a stomach that consists of two parts, the gastric

glands and gastric muscular tendon is strong (gizzard).

 The stomach is called gastric digastrik.

Birds often stomach muscle meat filling with sand, gravel, or stones that are

intentionally swallowed to help grind the beans - seeds are eaten.

BACK

C. Poligastrik

• Poligastric is composed of more two rooms, a suborder of mammals found in ruminants.

• Poligastric ruminant stomach has 4 rooms, separated into two groups.

1. The first group consists of the rumen and reticulum. Rumen and reticulum Acting as a

fermentation chamber to food that is swallowed without chewing during grazing.

2. The second group consists of the omasum and abomasums (true stomach). The particles –

particles from rumen that are not digested, enter to omasum, and then into the abomasum. In there

occur true digestion like in monogastric. ^BACK

Digest and absorb nutrients

Small intestine



With a length of more than 6 m in humans, the small intestine is part of the most long digestive tract.



Small intestine is the organ where most of the enzymatic hydrolysis of macromolecules in food occurs.



This organ is also responsible for the

majority of nutrient absorption into

the bloodstream.

Defecation

Anus

 The anus is an opening at the opposite end of an animal's digestive tract from mouth. Its function is to control the

expulsion of feces, unwanted semi-solid matter produced during digestion.

In animal divided to two types of gut. There are :

 Like simple animal, such as sponges and cnidarians, the flatworms have two-way gut. (a) most flatworms, such as Macrotomum, process a simple gut with a single sack. (b) in some larger flatworm species, such as Dugesia, the gut can have three or more side branches with lateral

divercula.

7. GUT REACTORS

THEORY

Batch reactors

• Batch reactors receive a pulse of precursors and after a period of time convert the precursors into products. This is much like the two-way gut used by cnidarians, which engulfs and

digests food particles in a gastrovascular cavity, then expels undigested material.

2. Tank reactors

 Tank reactors receive a constant infusion of precursors and generate a constant stream of products. The fermentation chambers of some animals, such as the bird cecum or the cow

rumen, are examples of tank reactors.

3. Plug flow reactors

 In plug flow reactors, a bolus of precursors begins at one end of a tube-shaped reactor and moves

through the tube to the other end. The intestine of most animals works in this way, with food exiting the stomach and passing through the tubular

intestine to the anus.

THE END

diskusi

1. Paruh pada hewan dan jenis makanan

2. Hewan makan makanan basi ,bagaimana

?

3. fistula

4. Menelan gigi ?

5. Kambing makan jus daging dan rumput 6. Kecukupan protein hewani pada

ruminansia

7. Kucing makan roti dan rumput 8. Kerikil pada aves

9. Keelnjar dan enzim penecernaan pada invertebrata