bch 10 midterm study guide

Diet

usual pattern of foods

Nutrients and the 6 classes

Nutrients are life-sustaining substances in food that ensure ur body is functioning properly

1. Carbohydrates

2. Vitamins

3. Minerals

4. Protein

5. Sugar

6. Fats (lipids)

Metabolism

the chemical processes that take place in living cells which includes catabolism (generating energy) and anabolism (making molecules)

What is the most essential nutrient?

Water

Phytochemicals

substances found in plant foods that aren't labeled as nutrients

• some beneficial to health but not all

• plants make hundreds of these

Macronutrients

PROVIDES ENERGY for cells!!

• carbs, proteins, & fats

• needed in large amounts daily

micronutrients

DONT PROVIDE ENERGY

• vitamins and minerals

• help convert food into usable energy tho

• ex: vitamin C, B, iron, zinc

Empty calories

• high macros and calories

• low micronutrients

• junk food w/ lots of energy

Nutrient-dense food

• lots of micronutrients and not much energy (calories)

• should eay more nutrient dense foods

• ex: leafy greens, lean protein, some dairy

Malnutrition

includes undernutrition and overnutrition

• state of health that occurs when the body is improperly nourished

Whats the most common nutrition product?

dietary supplements

Dietary supplements

Classified as food not as drugs

they include:

• nutrient pills

• protein powers

• herbal extracts

• energy bars

Undernutrition

• wasting

• lacking vitamins and minerals

overnutrition

• overweight

• obesity

• heart disease

• diabetes

Are nutrition facts panels on all foods?

No!!

• not required on fresh fruits, veggies, fish, and shelfish

• bc they arent foods of concern

Daily values

How much nutrient in a single serving of an individual packaged food or dietary supplement contributes to your daily diet

what amount of calories is the daily value based on?

a 2000 cal a day

What is the rule of thumb for nutrutuon facts panel?

5% DV or less of a nutrient per serving = low

5-20% = moderate

20% or more = high

How do u calculate fat , carb, protein, sodium, etc. percentage left for one day?

bc goal to reach 100% for each:

100% - the DV %

What are the what “nots”

• added sugars

• saturated fats and trans fat

• sodium

What is the recommended intake for added sugars?

• sugars/syrups added

  • doesnt include natural sugars

  • empty cals

    • <10% of total cal intake

What is the recommended intake for saturated fats and trans fat?

• RDA or CDR: <10% total cal intake

What is sodium and what is the recommended intake?

• used as a preservative for processed foods

• a mineral found in salt

• a micronutrient bc doesnt give u energy

• RDA or CDRR: <2300/mg per day

how can you calculate sodium?

(Xmg) / 2300mg x 100 =Y%

or if only given percentage: 2300 x (X%/100)= Y

What are organic foods?

• foods produced without antibiotics, hormones, synthetic fertilizers, pesticides, genitc improvements or spoilage killing radiation

• foods may be certified w/ FDA symbol

Are organic foods more nutritious?

Not really it just doesnt have extra additives

The dirty dozen and the clean 15

Every year fruits and veggies get tested to see which ones absorb the pesticides they are grown with

Are all dietary supplements FDA approved?

No and it will give a disclaimer on the supplement facts in the back if it has or hasnt

Nutrient-dense food vs supplements, which is better?

Nutrient dense food always!!

Supplements take longer to absorb, more expensive, easy to megadose, may not provide all necessary nutrients, and they arent strictly regulated in comparison to food.

What is the smallest living unit in the human body?

A cell!

What is in a cell?

organelles that each have a special function

ex: ribosomes, nucleus, mitochondria, etc

where is DNA found in a cell?

the nucleus

What are tissues?

a collection of sells that perform specialized functions

ex: connective tissues holding stuff together to protect and support organs

• (bones, fat, blood)

What is an organ?

A collection of diff types of tissues that perform a specific function

What is the organ system?

a collection of organs working together to perform a major function

How are cells and organ systems connected?

cells—> tissues—>organs—>system

• tissues made up of cells

• organs made up of tissues

• organ system (lots of diff organs made up of those tissues and cells)

what are cells made of?

Molecules which includes carbs, proteins, DNA, and lipids

WE ARE WHAT WE EAT

How do cells get nutrients?

From food that is broken down into nutrients

Metabolism

the chemical reactions that occur in living cells

• happens at the cellular level!!

• includes catabolism and anabolism

Catabolism

metabolic processes that break down molecules

anabolism

metabolic processes that builds molecules

What are enzymes?

proteins that make chemical reactions go faster like in metabolism and digestion

What are chemical reactions?

processes that change atomic arrangement in molecules

How can I decipher an enzyme?

It usually ends in “ase”

ex: sucrase and lactase

What happens in digestion?

molecules in food are mechanically and chemically broken down

what are molecules made of?

atoms which are elements

do humans make minerals?

NO the minerals are elements found in the earths crusts (ex: calcium, iron, zinc)

what is a chemical bond?

an attractive force that holds atoms together to form molecules

- bonds can be single, double, or triple—> look at the lines between atoms

ex: O=O or H-O-H

What is the lymphatic system?

A sewer system that helps process fat

• helps maintain fluid balance

• absorb fat soluble nutirents

• defends body against disease

• includes: lymoh nodes, spleen, etc

What us the main function of our digestive system?

to break down large food particles into smaller nutrients and absorb these nutrients into the blood stream or into the lymphatic system

What are the main organs of our digestive system?

mouth, esophagus, stomach, large intestine and small intestine

what is the gastrointestinal tract?

a muscular tube from the mouth through the whole digestive system to the anus

what is bioavailability?

the extent to which the digestive tract absorbs a nutrient and how well the body uses it

Where does digestion begin?

The mouth!

• mechanical and chemical digestion happen here

Mechanical digestion

the biting and grinding actions that break down and mash food into smaller pieces

Chemical digestion

our saliva lubricates the food and the amalase enzyme begins breakdown of starch in the mouth

lingual lipase also breaks down fat in stomach

Are enzymes proteins?

YES

How are our taste and smell part of digestive system?

our tastebuds on our tongue, lining of mouth and throat communicate w/ our brain that it tastes good or bad

smell

• the chemicals in our food become airborne and stimulate olfactory receptor proteins on cells in nasal passages

Esophagus and swallowing

our esophagus is a tube connecting pharynx with our stomach

to prevent choking when we swallow, there is a flap called the epiglottis that folds over our windpipe and voice box

What is in our stomach?

Gastric juice, chyme, and mucus

Gastric juice

made up of hydrocloric acid and enzymes which kill most microbes from food

Chyme

mix of gastric juice and partially digested food bits in the stomach

What does mucus do in the stomach?

it lubricates the stomach walls to protect it from gastric juice

Where are most nutrients digested and absorbed?

the small intestine!!

What happens in the small intestine?

• nutrients are absorbed from the chyme which takes like 3-5 hours to get through

• the villi catch the nutrients and transport it to the bloodstream

• the absorbitive cells remove nutrients from chyme and transfer into intestinal blood or lymph

Villi

baby cells that line the small intestine

• catch the nutrients and transport it to the bloodstream

Why are absorbitive cells in small intestine always dying

just have a short life span but can be impacted by our diet too

ex: spicy foods

what is the goal of digestion?

to break down and give to cells

What are accessory organs for digestion? What are the 3 organs?

These dont come into contact with chyme (gastric juice + food)

1. liver

2. gallbladder

3. pancreas

What is the role of the liver in digestion?

water-soluble nutrients enter thevilli and travel here through a portal vein

It processes and stores many nutritents

It makes cholesterol (waxy fat substance) and bile (a fluid)

What is the role of the gallbladder in digestion?

• stores and secretes bile (a fluid that aids fat in digestion)

• Gallstones (pellets of cholesteral) can form here and block bile duct

What is the role of the pancreas in digestion?

makes digestive enzymes and bicorbonate ions that increase pH

• produces hormones like glucagon to send message to body

What are hormones?

messengers in our body

large intestine

composed of colon and rectum

where the absorption of WATER and MINERALS occur

feces form from chyme that became semi-solid

has friendly bacteria

what helps carry out processes in the large intestine?

fiber!

what does friendly bacteria/ gut microbes in the large intestine do?

• metabolize undigested food material

• make vitamins and biotin

• produce gas

• the bacteria is good for health

• bacteria is excreted in feces

Probiotics

live beneficial intestinal microbes

found in yogurt, fermented foods

complemntary medicine not prescribed

Prebiotics

form of dietary fiber that supports growth of beneficial gut microbes

Are human digestive tracts adaptable?

yes! the digestive enzymes help us break down chemical reactions and foods and bile helps us process fat

what are the leading causes of death in the US?

1. Heart disease

2. Cancer

3. Stroke

4. Type 2 diabetes

What are carbohydrates?

major source of ENERGY

they arent made by our body so we consume them

How are carbohydrates made?

made by plants through photosythesis then built into larger structures via chemical reactions

(photosythesis is where plants absorb CO2 and H2O, capture light energy from sun and converted into simple sugars)

How can carbs be identified?

they end in “-ose”

ex: glucose, fructOSE

what are the 3 types of carbohydrates?

• sugars

• starch

• fiber

what are simple carbs

sugars or saccharides

• can be monosaccharide:1

• or disaccharides: 2

• simple bc they are all spaced out and its structure isnt chaogtic

What are the monosaccharides (a simple carb)

Glucose, fructose, galactose

Glucose

primary enegry source for cells

fructose

main sugar in fruits

Galactose

part of milk sugar—> aka lactose

what is the formula for all 3 monosaccharides?

carbon, hydrogen, oxygen

they have same formulas but different chemical bonds and structures and ur absorption cells can tell the difference of the sugars

what are the smallest units of carbs?

monosaccharides

How do carbs enter the bloodstream?

they have to be broken down from disaccharides to monosacchrides

what is the most important monosaccharide in the human body?

glucose!

• glucose fuel for many cell types

• red blood cells, brain cells, and nervous system cells need glucose

• other carbs can be converted into glucose to harvest energy

carb-free diets

dangerous!! we need carbs for energy

what are disaccharides?

a simple sugar made of 2 monosaccharides

includes maltose, sucrose, and lactose

ALL MADE WITH GLUCOSE

Maltose

glucose + glucose = starch

starchy foods: potaoes and pasty

starch doesnt taste sweet to us

sucrose

glucose + fructose

• table sugar!

lactose

glucose + galactose

• milk sugar

how is table sugar aka sucrose made?

from sugar canes (CANYA) or sugar beets that are refined and take away any vitamins and minerals

where else is sucrose found besides table sugar?

in honey (natural), maple syrup and other fruits and veggies