bio chap 47 condensed

What is nutrition + its role?

Study of nutrients; supports metabolism, homeostasis, growth, reproduction

4 processes of nutrition

Ingestion, digestion, absorption, elimination

Herbivores vs carnivores vs omnivores

Plants / animals / both

4 feeding METHODS

Fluid, suspension, deposit, bulk

Examples of feeding methods

Fluid (mosquito), suspension (whale), deposit (earthworm), bulk (humans)

calorie vs Calorie

1 Calorie = 1000 calories

Energy per gram (carb, protein, fat)

4, 4, 9 kcal

3 types of malnutrition

Undernutrition, overnutrition, micronutrient deficiency

Organic vs inorganic nutrients

Organic = carbs, proteins, lipids, vitamins; Inorganic = minerals

Essential nutrients definition

Must be obtained from diet

Essential fatty acids

Linoleic + linolenic

Intracellular digestion example + process

Sponges; endocytosis → lysosome digestion

Extracellular digestion + advantage

Occurs in lumen; allows large food intake

5 steps of digestion

Mechanical, secretion, hydrolysis, absorption, elimination

GI tract pathway

Mouth → pharynx → esophagus → stomach → small intestine → large intestine → rectum → an

Accessory organs

Salivary glands, liver, pancreas, gallbladder

Main functions of stomach

Storage, mechanical digestion, protein digestion, intrinsic factor

Enzyme for protein digestion

Pepsin

Stomach cell types

Chief (pepsinogen), parietal (HCl + intrinsic factor)

Functions of HCl

Low pH, kills bacteria, activates pepsin

small intestine % absorption + key structure

90%; villi + microvilli

3 parts of small intestine

Duodenum, jejunum, ileum

Duodenum function

Mixing chyme + enzymes + bile

Jejunum function

Main absorption

Pancreas role

Enzymes + bicarbonate (neutralize acid)

Liver + bile

Emulsifies fats

What lipase does

Breaks fats → fatty acids + monoglycerides

large intestine Main functions

Water reabsorption, feces formation

large intestine Bacteria produce what?

Vitamin K + B vitamins

Fat vs water soluble vitamins

Fat (A,D,E,K); Water (B,C)

Special vitamins produced in body

D (skin), K (gut bacteria)

Iodine function + deficiency

Thyroid; deficiency = goiter

Iron + calcium roles

Iron = hemoglobin; Calcium = bones + muscles

4 layers of gut

Mucosa, submucosa, muscularis, serosa

Peristalsis definition

Wave contractions moving food

Important sphincters (order)

Upper esophageal → lower esophageal → pyloric → ileocecal → an

Mouth digestion

Mechanical + salivary amylase (starch)

Epiglottis function

Prevents food entering airway

Esophagus movement

Peristalsis

Stomach product

Chyme

Amylase, protease, lipase functions

Carbs, proteins, fats

Where nutrients go after absorption

Blood (water-soluble), lymph (fats)

Lactose intolerance cause

Lack of lactase → gas/bloating

Liver functions (3)

Glycogen storage, detox, lipid transport

Colon sections

Ascending, transverse, descending, sigmoid

Rectum function

Stores feces

Gastrin function hormone

↑ stomach acid + activity

Secretin function

↓ stomach acid, ↑ bicarbonate

CCK function

↓ stomach, ↑ enzymes

GIP function

↑ insulin

Leptin vs ghrelin

Leptin = full; Ghrelin = hungry

Peptide YY

Satiety hormone

GERD cause

Acid reflux (lower esophageal sphincter)

Microbiome definition

All microbes in body

Cellulose digestion

Requires bacteria (cellulase)

4 stomach chambers

Rumen, reticulum, omasum, abomasum

Where cellulose digestion occurs

Rumen + reticulum

Cud definition

Regurgitated food re-chewed

Earthworm digestion path

Mouth → crop → gizzard → intestine → an

Insect digestion key part

Gastric ceca

Bird digestion key structures

Crop (storage), gizzard (grinding)

Choanocytes location + function

Sponges; intracellular digestion

Humans feeding

Bulk feeders

Iodine deficiency causes

Goiter

1 Calorie equals

1000 calories

Vitamins made in body

D and K