Download H U M A N N U T R I T I O N 1. * NUTRIENTS: *substances our body

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1. * NUTRIENTS: *substances our body needs to grow, survive and repair itself
*give us energy
NUTRITION AND HEALTH
* 3 MOST IMPORTANT TYPES OF NUTRIENTS:
1 - CARBOHYDRATES: give us energy.
>>>>>> Two types: -SUGARS: found in foods that taste sweet
-STARCHES: found in bread, potatoes and legumes
2 - FATS: give us energy.
>>>>>>>>> >>>>>> Two types: -ANIMAL FATS: butter, bacon
-PLANT FATS: olive oil, sunflower oil
3 - PROTEINS: help our body grow and repair itself.
Sources: meat, fish, legumes
2. * OTHER NUTRITIVE SUBSTANCES:
- VITAMINS AND MINERALS: we need small amounts, but they are essential. Sources: fruits and vegetables; milk (calcium for strong bones)
- WATER: most of our body is made of water. We need to compensate the water we lose in urine, transpiration, etc. drinking water or eating food
- FIBER: Help food to move through the digestive system. Sources: fruits, vegetables, whole-grains
3. * DIET: is the food that someone normally eats over a period of time. A Healthy diet is complete and balanced:
* Complete: include nutrients from all the food groups
* Balanced: include the right amount of each nutrient
4. * RECOMMENDATIONS FOR A HEALTHY DIET: * Eat foods from all the food groups * Decrease your intake of candy, desserts and soft drinks (they provide empty
calories!) * Avoid animal fats (bad for the circulatory system!) * Eat lots of fresh fruit and vegetables >> contain vitamins and fiber * Chose whole wheat, bread and
pasta>> contain fiber * Eat more fish and chicken and less meat or beef >> have less fat
* THE DIGESTIVE PROCESS: * converts the food we eat into nutrients that our body can absorb
THE DIGESTIVE PROCESS
* takes place in the digestive system
* has 3 phases:
1 - DIGESTION
2- ABSORPTION
3- ELIMINATION OF WASTE SUBSTANCES
* THE DIGESTIVE SYSTEM: *has two parts: *the digestive tract: - the food we eat passes through this tube
- divided into various parts
- each part has a specific function
- begins in the MOUTH and ends in the ANUS
*annex glands:
- secrete liquids into the digestive tract, they are: - SALIVARY GLANDS - LIVER - PANCREAS
P H A S E S:
1. * DIGESTION: * process which breaks down foods to obtain nutrients
* parts of the digestive system that take part in the digestive process:
>> MOUTH:
>> teeth break food into small pieces and chew them >> pieces are mixed with saliva produced by the salivary glands >> bolus is
formed (= mass of chewed, soft food)
>> ESOPHAGUS:
>> the bolus moves down the pharynx (throat) >> and the esophagus >> and passes into the stomach
>> STOMACH:
>> the bolus is mixed with the gastric juices that the stomach produces (thanks to the muscle action of the stomach walls) >>
produces a thick liquid called chyme
>> SMALL INTESTINE: >> the chyme leaves the stomach and enters the small intestine >> intestinal walls produce intestinal juices >> intestinal juice +
x
juice from the pancreas + bile from the liver = finish digesting the chyme >> and finally a milky fluid called chyle is
x
produced
2. * ABSORPTION: * process in which nutrients pass from the digestive system into the blood
* takes place in the small intestine
* walls of the small intestine are covered by finger-like projections called villi. They increase absorption
* each villus has blood vessels. They absorb and transport nutrients beyond the intestinal wall
3.* ELIMINATION OF WASTE: * EGESTION is the elimination of undigested food substances
* the chyle loses nutritional value as it passes through the small intestine
* undigested substances remain and move on the large intestine
* large intestine extract water from these substances and form solid waste called feces
* we expel feces through the anus
* RESPIRATION : * is the movement of air IN and OUT of the body to OBTAIN oxygen and EXPEL carbon dioxide
RESPIRATION
* this function is carried out by:
* THE RESPIRATORY SYSTEM: * is made up of: * nose * mouth * lungs (2 spongy organs in the thoracic cavity, they contain: bronchi, bronchioles, alveoli
x
and many blood vessels) * air passageways (tubes which carry air into and out the body)
* Humans breathe: air must enter and leave the lungs through:
* Breathing or respiratory movements:
INHALATION: - air enters the body
EXHALATION: - air leaves the body
- lungs and thoracic cavity expand
- lungs and thoracic cavity contract
- this pull the air with oxygen through the air passageways
- this pushes the air from the lungs up through the air
x
to the alveoli
passageways and out of the body
- in the alveoli OXYGEN passes into the blood
- this air contains less OXYGEN and more CARBON DIOXIDE
- and CARBON DIOXIDE leaves the blood and passes to the
x
alveoli
* Muscles like the diaphragm (separates the thorax from the abdomen) and the intercostal muscles between the ribs are involved in the respiratory movements
* THE RESPIRATORY PROCESS: * begins in the nose >> pharynx >> larynx >> trachea that branches into 2 main: >> bronchi (1 for each lung) that
divided into smaller: >> bronchioles with tiny sacs at the ends, called: >> alveoli
* EXCRETION: * is the elimination of waste substances from the blood
EXCRETION
* this process is carried out by the:
* EXCRETORY SYSTEM: * is made up of: 1* KIDNEYS
2* URETERS (that go from the kidneys to the urinary bladder)
3* URINARY BLADDER
4*URETHRA (that go from the urinary bladder to the outside of the body)
*URINARY PRODUCTION: * The kidneys filter the blood, retain waste substances and use them to produce urine >> ureters carry urine from kidneys to >> the
x
urinary bladder (store the urine) >> urine leaves the body through the urethra
* CIRCULATION: * is the movement of blood through the circulatory system to transport nutrients, oxygen and waste
BLOOD CIRCULATION
* THE CIRCULATORY SYSTEM: * is made up of:
* heart
* blood * blood vessels (are tubes that transport blood)
* HEART: * is a hollow organ with very muscular walls * it works like a pump * it moves blood through the body
* BLOOD: * is a red liquid that transport substances throughout the body
* is made of PLASMA (liquid part) and two types of:
BLOOD CELLS: Red blood cells:
* are the most numerous
* they distribute oxygen and make blood red
White blood cells:
* form part of our immune system
* they fight infection and protect the body of illness
*BLOOD VESSELS: There are 3 types:
ARTERIES: - Carry the blood AWAY from the heart to the organ
VEINS: - Carry the blood from the organs TO the CAPILLARIES: -Connect arteries to veins
-Arteries close to the heart are bigger
heart
-They are the smallest blood vessels and
-Arteries far from the heart are smaller and have many
- Veins close to the heart are bigger and thicker
have very tiny walls
branches
than the veins far from the heart
*BLOOD CIRCULATION: Blood moves through the circulatory system in a close circuit. There are two CIRCULATORY SYSTEMS:
PULMONARY CIRCULATION: * is the movement of
SYSTEMIC CIRCULATION: * is the movement of blood to the rest of the body
blood between the heart and the lungs
* blood with oxygen from the lungs leaves the heart through the artery aorta and
* blood leaves the heart through the pulmonary
returns to the heart through the vena cava
arteries
x and returns to the heart through the
*blood picks up substances from digestion in the small intestine
pulmonary veins
*blood distributes OXYGEN and nutritive substances and picks up CARBON DIOXIDE and waste
substances, as it travels through the body