Unit 4: Internal Systems and Regulation Flashcards
What is DIGESTION?
The process of mechanically and enzymatically breaking down food into substances for absorption into the bloodstream
What is ORAL CAVITY?
The first portion of the digestive system (the mouth)
- Teeth
- Tongue
- Soft and hard palate
For eating and speaking
What is PHARYNX?
The cavity that connects the oral cavity (mouth) and nasal cavity to the esophagus, trachea, and larynx region
Passageway for air to enter the larynx and lungs and food and liquid to enter the esophagus
What is EPIGLOTTIS?
Flap of cartilage located in the throat behind the tongue and in front of the larynx.
Seals off the trachea (windpipe) during eating, so that food/drink is not accidentally inhaled
What is ESOPHAGUS?
Muscular tube that transports food/liquid from the throat to the stomach
What is GASTRIC JUICE?
- Combination of hydrochloric acid (HCl), lipase, and pepsin
- Inactivates swallowed microorganisms, thereby inhibiting infectious agents from reaching the intestine.
- Acid released into the stomach by glands in the stomach wall
Job of STOMACH? Structure?
- Produces enzymes and acids (stomach acid) to break down food (chemical digestion)
- Churns food to break it down (mechanical digestion)
J-Shaped organ (has mucous cells that protect stomach lining, digestive juices inside for chem digestion, has muscle for mech. digestion)
Job of SMALL INTESTINES? How does it DIGEST so much? Structure?
Digesting food, transporting food, absorbing nutrients from the food
Has many folds (mucosal folds), villi, and microvilli -> all increase the surface which allow it to absorb more nutrients
Long and coiled with three sections (duodenum, jejunum, ileum)
Job of LARGE INTESTINES? Structure?
Reabsorb water and electrolytes (salts) and get rid of left over waste (poop)
Larger tube, goes around small intestines, contains colon, rectum, and anus. (ascending, transverse, descending)
What does PANCREAS do?
Produces digestive juice with pancreatic enzymes to break down foods (aids in chemical digestion)
What does GALL BLADDER do? Structure?
Stores and concentrates bile from the liver
Small, located under liver
Made of several tissue layers
3-4 inches long and 1 inch wide
Tapered at one end (pear shaped)
What does LIVER do? Structure?
Filters/cleans blood that leaves the stomach and intestines
Removes waste from blood which will leave through urine or feces
2 main lobes
Very large organ
Top connects to heart, bottom connects to stomach
What does SALIVA do?
Helps with digestion (helps to chew and swallow food)
Breaks down starch using salivary amylase (enzyme)
What is an ENZYME?
Protein that speeds up metabolism/the chemical reactions in the body (biological catalyst)
What is PEPSIN? What does it do?
Type of PROTEASE (category of enzyme that breaks down proteins) and breaks down food proteins into smaller peptides
What is PERISTALSIS?
muscle contractions and relaxations which push food down to stomach through esophagus to stomach to intestines to rectum
all throughout the digestive tract -> moves stuff
INHALATION vs EXHALATION
Inhalation is taking IN air (oxygenated)
Exhalation is giving OUT air (carbon dioxide-rich)
The two go hand in hand as the basic processes of breathing
OPEN vs CLOSED CIRCULATION
OPEN
- blood flows freely through cavities as there are no vessels to conduct blood
- primarily found in invertebrates (e.g. grasshopper)
CLOSED
- blood flows through a system of vessels which guides the blood through the body
- primarily found in vertebrates (and some invertebrates like earthworms)