Science Quiz (4th Quarter)

say no to this

continuous tube that begins at the mouth and ends at the anus

digestive system

in the average adult, how long is the digestive system?

about 30 feet

the digestive system is also known as the ____________

alimentary canal or gastrointestinal tract

what are the three functions of the digestive system?

1. the digestion of food into nutrients

2. the absorption of nutrients into the bloodstream

3. the elimination of solid wastes

what do salivary glands excrete?

saliva

the entry point of food

mouth or oral cavity

other term for chewing

mastication

the three pairs of salivary glands in the mouth

1. parotid

2. sublingual

3. submandibular

muscle in the oral cavity that is covered in a mucous membrane

tongue

what is the tongue covered in?

papillae (plural); raised elevations

what do the papillae contain?

taste buds (gustatory cells)

five basic taste sensations

sweet, sour, salty, bitter, & savory (umami)

used for chewing the food (mastication)

teeth

broken-down food mixed with saliva

bolus

soft palate at the back of the throat

pharynx

flap that closes the windpipe upon swallowing the food

epiglottis

muscular tube that is about 25 cm long

esophagus

series of involuntary, wavelike muscular contractions that move food in the digestive system

peristalsis

this sphincter is at the opening of the stomach

lower esophageal sphincter

it is a muscular, expandable organ located on the left side of the upper abdomen

stomach

upper portion of the stomach

fundus

lower portion of the stomach

antrum

What type of acid is in the stonach and what is its pH level?

Hydrochloric acid; pH level of 1-2

semi-liquid food mass

chyme

sphincter valve at the BOTTOM of the stomach, into the small intestine

pyloric sphincter

three segments of the small intestine

1. duodenum

2. jejunum

3. ileum

about 21 feet long and 1 diameter; extends from the pyloric sphincter to the large intestine

small intestine

foot-long section just beyond the stomach

duodenum

next 8 feet after duodenum

jejunum

remaining 12 feet of the small intestine

ileum

a yellowish-brown fluid that aids chemical digestion

bile

this accessory organ produces bile/gall

liver

where does bile travel through?

hepatic ducts

the function of bile

helps digest fats

some of the (excses) bile is also stored in the _________

gallbladder

the liver also stores what?

iron, and vitamins A, D, E, K (ADEK)

a green, pear-shaped sac that is about 10 cm long, stores and concentrates excess bile

gallbladder

what does the gallbladder do to bile?

it concentrates it and intensifies its potency

long, narrow gland that stretches from the spleen to about halfway through the duodenum

pancreas

what does the pancreas excrete?

pancreatic juice

pancreatic juice contains what?

digestive enzymes & bicarbonate ions

without _____________, we would starve, even if we ate an adequate amount of food

pancreatic juice

(small intestine) the jejunum and ileum are lined with what?

villi (singular: villus);

the function of villi inside the intestine

absorbs nutrients

(villi) collects amino acids and glucose

Villus capillaries

(villi) collect absorbed fatty acids

Villus lacteals

absorbs the remaining water and nutrients from indigestible food matter; stores waste, and eliminates waste

large intestine

other terms for large intestine

1. bowel

2. colon

segments of the large intestine

1. cecum

2. ascending colon

3. transverse colon

4. descending colon

5. sigmoid colon

where the feces are stored

rectum

the source of materials needed for the body to live and be healthy

food

what do we get from food?

nutrients or potential chemical energy

the potential chemical energy from food is converted into _____________

kinetic energy (energy in movement)

this happens when an organism is resting/inactive

energy Ploss (dissipated power)

Macronutrients

1. carbohydrates

2. fats

3. proteins

Micronutrients

vitamins & minerals

main source of energy for humans

carbohydrates

amount of energy is usually measured in _______

calorie (cal) - the amount of power needed to raise one gram of water by 1 degrees celsius

a person needs ________ calories per day

1500

refers to the chemical reactions that take place in the body

metabolism

amount of energy needed when the body is in complete rest; also a measure of how fast the chemical reactions take place

basal metabolism

_____________ normally have a higher basal metabolic rate

growing children

female young adult in her early 20’s

1800-2000 calories per day

male young adult in his early 20’s

2200-2500 calories per day