Nutrition Chapter 4-6

Catabolism

The sum total of all processes in an organism which break down chemicals to produce energy and simple chemical building blocks.

Chyme

mixture of gastric juice and partially-digested food

Mucus

lubricates and protects stomach walls

What does the liver do?

Makes bile, metabolizes macronutrients, stores some nutrients, and detoxifies alcohol/everything

What does the gallbladder do?

stores and concentrates bile

What does the pancreas produce?

insulin, enzymes, bicarbonate

What does the large intestine do?

Absorbs water and electrolytes; stores and houses bacteria

Similarities in the major 3 lipids

1. Insoluble in water (less dense)

2. Provides food with: flavor, texture, aroma

3. Provides body insulation, helps transport fat-soluble vitamins (ADEK), and line cell membranes

Absorption

Process by which substances are taken up into the bloodstream or cells after digestion.

Digestion

The process by which food is broken down into smaller components, enabling absorption of nutrients into the bloodstream.

Anabolism

The metabolic process that builds larger molecules from smaller ones, using energy to synthesize complex molecules like proteins and nucleic acids.

Enzyme

A biological catalyst that accelerates chemical reactions in the body, crucial for digestion and metabolism. ( ends in -ase)

Cardiovascular System

The system is responsible for the circulation of blood and lymph throughout the body, consisting of the heart, blood vessels, and blood.

Respiratory system

The system is responsible for the exchange of gases, including oxygen and carbon dioxide, between the body and the environment, primarily involving the lungs and airways.

Lymphatic (Immune) system

The system that helps defend the body against infection and disease, consisting of lymph nodes, lymph vessels, and lymph fluid.

Urinary system

The system is responsible for the elimination of waste products from the body, regulating fluid and electrolyte balance, primarily involving the kidneys, ureters, bladder, and urethra.

Muscular system

The system that enables movement of the body and maintains posture, consisting of skeletal, smooth, and cardiac muscles.

Skeletal System

The system that provides structure and support to the body, protects internal organs, and facilitates movement, consisting of bones, cartilage, and joints.

Nervous system

The system that coordinates and regulates body activities by transmitting signals between different parts of the body, consisting of the brain, spinal cord, and nerves.

Endocrine system

The system that regulates bodily functions through hormones, maintaining homeostasis, and includes glands such as the pituitary, thyroid, and adrenal glands.

Bio-availability

The degree to which nutrients or bioactive compounds are absorbed and utilized by the body after ingestion.

Chemical digestion

The process by which food is broken down into smaller components through enzymatic action in the digestive tract, allowing for nutrient absorption.

Mechanical digestion

The physical breakdown of food into smaller pieces, increasing the surface area for enzymes to work during chemical digestion.

What starts the digestion of starch?

Salivary amylase begins the digestion of starch in the mouth.

Epiglottis

A flap of tissue that covers the trachea during swallowing, preventing food from entering the airway.

Esophagus

The muscular tube that connects the throat (pharynx) with the stomach, facilitating the movement of food through peristalsis.

Persistalisis

The wave-like muscle contractions that move food through the digestive tract, primarily occurring in the esophagus and intestines.

Spincters

Muscle valves that regulate the passage of food or fluids between different parts of the digestive tract, ensuring proper digestion and preventing backflow.

Lower esophageal spincters (LES)

A ring of muscle at the junction of the esophagus and stomach that prevents the backflow of stomach contents into the esophagus.

Glycolysis

Lipolysis

Breakdown of lipids for energy

Glucagon

Made by alpha cells, opposes insulin (raises blood glucose)

Glycogenolysis

Glycogen breakdown, releasing it to the bloodstream

Gluconeogenesis

Making glucose from non-carb sources (protein/fat)

Ketone bodies

Byproduct of incomplete fat breakdown

Ketoacidosis

Condition of very high blood acidity

Villi

Tiny, finger like projections of small intestinal lining that participate in digesting and absorbing food

microvilli

A brush border that is made up of microscopic cells

Prebiotics

Forms of dietary fiber that are poorly digested by humans.

Probiotics

Live, beneficial gut microbes that have been cultured under lab conditions.

Type 1 diabetes

• autoimmune disease

• Beta cells stop making insulin

Type 2 diabetes

• Most common type

• Insulin Resistant cells

Type 1 diabetes treatment

• Requires treatment with insulin

• Needs a carb controlled diet

• Need daily self testing of blood glucose

Cholesterol

Makes vitamin D and sex hormones

chylomicrons

Lipoprotein that carries dietary fat

LDL (Low density lipoproteins)

“Bad” cholesterol; transports oxidized cholesterol to cells, but can deposit this in the walls of your arteries. Think as in trash can

HDL (High density lipoproteins)

“Good” cholesterol; smallest and densest lipoprotein. Can remove cholesterol from your blood and deliver it to the liver to be excreted. Think like a pickup truck for LDL (trash cans)

Stomach

A holding and a mixing tank; contains juices with HCL

Small intestine

The majority of digestion/absorption occurs here; contains villi

Large intestine

Absorbs water and electrolytes; houses the gut microbiome