fetal pig dissection prep -...
TRANSCRIPT
Fetal Pig Dissection Prep
A Review of Major Organs and Organ Systems
1
The Digestive System
■ Every cell requires a constant supply of nutrients and energy.
■ i.e. food
■ DIGESTION – the breakdown of food by mechanical and chemical means.
■ The digestive tract and the accessory organs of digestion make up the digestive system
■ The DIGESTIVE TRACT is a hollow tube extending from the mouth to the anus
■ It is also called the ALIMENTARY CANAL or the GASTROINTESTINAL (GI) TRACT
The Digestive Tract…■ Structures of the digestive
tract: ■ Mouth (oral cavity) ■ Pharynx (throat) ■ Esophagus ■ Stomach ■ Small intestine ■ Large intestine ■ Rectum ■ Anus
The Accessory Organs…■ The accessory
organs include: ■ Salivary glands ■ Teeth ■ Tongue ■ Liver ■ Gallbladder ■ Pancreas
Mouth■ The digestive tract
begins with the MOUTH, also known as the ORAL CAVITY or BUCCAL CAVITY
Mouth■ The mouth contains structures that
assist in the digestive process: ■ Teeth ■ Tongue ■ Salivary glands ■ Hard palate ■ Soft palate
Teeth■ MASTICATION –
the process of chewing
■ Teeth rip and grind food
Tongue■ TONGUE – a muscular
organ that occupies the floor of the mouth ■ Mixes food ■ Pushes the food toward the
pharynx ■ Taste buds allow us to enjoy
food ■ Speech forming consonants ■ Lingual frenulum: fold of
membrane that secures tongue to floor of mouth
Tongue■ Tongue-tied: distorted speech due to
shortened frenulum
Salivary Glands3 pairs of SALIVARY GLANDS secrete their contents into the mouth ■ AMYLASE enzyme to begin breakdown of starch ■ Cleanses mouth ■ Antibodies to inhibit bacteria
Pharynx■ The tongue pushes
the food from the mouth into the PHARYNX (throat)
■ The pharynx is involved in swallowing
Esophagus
■ ESOPHAGUS – a long tube that carries food from the pharynx to the stomach
Stomach
■ Stomach: C-shaped organ
■ Lies in the abdominal cavity, just under the diaphragm
Functions of the stomach…1. digestion of food 2. secretion of gastric (stomach) juice, which
includes digestive enzymes, and hydrochloric acid as its most important substances
3. secretion of gastric hormones and intrinsic factor
Regions of the stomach…■ FUNDUS ■ BODY ■ PYLORUS
Regions of the stomach…Two sphinctors ■ PYLORIC
SPHINCTOR regulates the rate that gastric contents are delivered to the small intestine
Regions of the stomach…■ CARDIOESOPHAGEAL
SPHINCTER ■ Between esophagus and
stomach
Small intestine■ Chyme enters in
small amounts due to pyloric sphincter ■ Most food is absorbed
in small intestine ■ High surface area
Large Intestine■ Larger diameter,
shorter in length ■ Dries out food by
absorbing water ■ Eliminates food
residue (feces)
■ Cecum ■ Appendix ■ Ascending colon ■ Transverse colon ■ Descending colon ■ Sigmoid colon ■ Rectum ■ Anal canal ■ Anus
Liver
■ Liver: large, reddish-brown organ located in the upper abdominal cavity
■ All blood from digestive system enters liver first
■ HEPATIC refers to liver
Liver ■ Produces bile to break up (emulsify) fat ■ No bile or lipase, no fat absorption ■ Detoxification of drugs ■ Metabolism of carbohydrates, proteins,
fats
Gallbladder■ Located underneath
liver
■ Stores bile
■ Gallstones: crystallized bile
Pancreas■ Both endocrine and exocrine
secretions ■ The exocrine secretions include
digestive enzymes ■ Most important of all digestive
enzymes
Pancreas■ Enzymes
■ Amylase: carbohydrate breakdown ■ Lipase: fat breakdown ■ Trypsin, chymotrypsin, peptidases: protein breakdown ■ Nucleases: nucleic acid breakdown
Pancreas■ Hormones
■ Insulin: brings glucose into cells
■ Glucagon: releases glycogen from liver
Organs of the respiratory system■ Nasal cavity ■ Nasopharynx ■ Larynx ■ Trachea ■ Bronchi ■ Lungs
Nose and Nasal Cavities
■ Sense of smell ■ Warms the air ■ Mucus to trap bacteria & debris ■ Ciliated cells move mucus toward throat ■ Separated from mouth by the palate
Pharynx – the Throat
■ Includes:
1. Nasopharynx
2. Oropharynx
■ The pharynx conducts food toward the esophagus and air to the larynx
Larynx
■ Also called the VOICEBOX is located between the pharynx and the trachea
Has 3 functions: 1. Passageway for air 2. Produces sound 3. Prevents food and other
foreign objects from entering the trachea
■ Food and water should not enter the larynx
■ How is food and water kept out of the larynx?
■ At the top of the larynx is a hole called the GLOTTIS
■ When you breathe in air, the glottis opens, and air moves through the glottis into the lungs
■ When you swallow food, a flap called the EPIGLOTTIS covers the glottis, sending food instead into the esophagus, preventing food from entering the respiratory passages
Trachea■ Also called the
WINDPIPE ■ Splits into the right/left
BRONCHI (plural), BRONCHUS (singular)
■ Conducts air to and from the lungs
■ Rings of hyaline cartilage maintain shape
Lungs■ Two LUNGS, located
in the thoracic cavity, extend from just above the clavicles to the diaphragm
■ Subdivided into lobes
■ Right lung has 3 lobes
■ Because of the location of the heart in the left side of the chest, the left lung only has 2 lobes
Lungs■ Alveloi
■ Site of gas exchange
■ The DIAPHRAGM is a muscle that forms the floor of the thoracic cavity and separates the thoracic cavity from the abdominal cavity
■ It is the chief muscle of respiration
The Heart and Cardiovascular System
Heart■ Hollow, muscular
organ made of cardiac muscle
■ Function: pump blood through the blood vessels of the body, providing every cell in the body with nutrients and oxygen
Pericardium■ The pericardium is
a serous membrane, secreting a slippery fluid into the pericardial space
Heart
■ The heart has 4 chambers: 2 atria and 2 ventricles
■ The ATRIA (singular ATRIUM) receive the blood – the upper chambers
■ The VENTRICLES pump the blood out of the heart – the lower chambers
Heart Chambers
The Endocrine System
Endocrine System■ Communicates through CHEMICAL
SIGNALS called HORMONES
■ Responds more slowly and generally exerts longer-lasting effects than the nervous system
Thyroid Gland■ THYROID GLAND –
located in the anterior neck
■ Thyroid hormone- controls rate at which glucose is burned
■ Calcitonin- deposits calcium into bone
Thymus■ Large in infants and
decreases size as adults
■ Programs T lymphocytes
Spleen ■ Immune system ■ Filters blood
Gonads ■ The GONADS are the sex glands
■ OVARIES in females
■ TESTES in males
■ The gonads not only produce eggs and sperm, they secrete hormones as well
Scrotum■ Holds the testes
outside of pelvic cavity
■ Sperm production must happen at a lower temp than body temp
Uterus■ Functions to receive
and nourish a fertilized egg
Urinary System■ Kidneys ■ Ureters ■ Urinary bladder ■ Urethra
Kidneys ■ Kidney bean shaped
organs ■ Under 12th rib ■ Cleanse blood of
waste products ■ Makes urine
Ureters ■ Tubes from kidney to
bladder
Urinary Bladder■ Sac that stores urine
Urethra ■ Carries urine from
bladder to outside