Transcript BC Science 8 Chapter 2

BC Science 8 Chapter 2
2.1
Body Systems
http://www.smm.org/tissues/
Systems:
A system is made of individual parts that work
together as a whole.
A system is usually connected to one or more
systems.
If one part of a system is missing or damaged, the
system will not function well or not at all.
If Grade 8 we will be dealing with only the
circulatory, digestive, respiratory, excretory, and
immune system.
Organ Systems:
Cell
Gland
Hormone
Nervous
blood
Tissue
Organ
Organ system
Muscle Tissue
Nerve Tissue
Connective
Epithelial Tissue
Heart
Lung
Circulatory
Organism
2.2
Digestive
http://www.argosymedical.com/Digestive/samples/animations/Digestion/index.html
(Digestion)
http://www.argosymedical.com/Digestive/samples/animations/Dual%20Roles%20of%20the%20P
ancreas/index.html
(Pancreas)
http://www.argosymedical.com/Digestive/samples/animations/Sherwood%20Swallowing/index.
html
(Swallowing)
http://www.youtube.com/watch?v=tat0QYxlCbo&feature=related
(Liver)
http://www.youtube.com/watch?v=TWUZx738OZM&feature=related
(Liver & Pancreas)
Excretory
http://www.youtube.com/watch?v=XF_lF3J4ZKs
Nutrients: substances the body requires for energy, growth,
development, repair and maintenance
-Carbohydrates: source of energy.
Simple (glucose) and
complex (chain of simple carbs – pasta, brown rice, and whole
grains).
-Protiens: build parts of body muscle, skin, hair and nails.
Fish, meat, poultry, nuts soy and diary.
-Fats: build cell membranes.
Butter oil, meat, milk.
Unsaturated fats are liquid at room temperature (corn oil, olive
oil.) saturated fat are solid at room temperature (butter). Eating
too much saturated fat can lead to plaque build up in arteries.
Sodium (Na) – nerve activity – (bacon, salt, butter)
Magnesium (Mg) – muscle and nerve activity, bone formation –
(fruit, veggies, grains)
Calcium (Ca) - muscle and nerve activity, teeth and bone
formation, - (milk, grains, calcium fortified o.j.)
Phosphorus (P) - muscle and nerve activity, teeth and bone
formation -(Milk, grains, veggies)
Copper (Cu) – development of red blood cells (grains, liver)
Potassium (K) - muscle and nerve activity, veggies and bananas
Sulfur (S) – hair, nails, and skin builder (Grains, cheese, eggs
fruits)
Water – not a nutrient but transports nutrients and wastes, cools
Vitamin A
This vitamin plays a really big part in eyesight:
night vision and color. It helps your body
fight infections by boosting your immune
system.
Source
-milk fortified with vitamin A
-liver
-orange fruits and vegetables (like
cantaloupe, carrots, sweet potatoes)
-dark green leafy vegetables (like kale,
collards, spinach)
The B Vitamins
The B vitamins are important in metabolic activity —
help make energy.
They also involved in making red blood cells, which
carry oxygen throughout your body.
Source:
-whole grains
-fish
-poultry and meats
-eggs
-dairy products
-leafy green vegetables
Vitamin C
This vitamin is important for keeping
body tissues in good shape. C helps
you heal. (i.e. a cut)
This vitamin also helps your body
resist infection.
Sources:
citrus fruits - oranges
sweet red peppers
Vitamin D
Need for strong bones and teeth. It
also helps your body absorb calcium.
Sources:
made in the skin when exposed to
milk fortified with vitamin D
fish
egg yolks
liver
Vitamin E
Protects your cells and tissues from damage. It is also important
for the health of red blood cells.
Sources:
whole grains
leafy green vegetables
vegetable oils like sunflower, canola, and olive
egg yolks
nuts and seeds
Vitamin K
Clotting of blood
Sources:
leafy green vegetables
dairy products, like milk and yogurt
broccoli
soybean oil
Four Stages: Ingesting, digesting, absorbing and eliminating
Enzymes: protien that helps speed up reations.
3 Enzymes you need to know about in gr 8: amaylase (mouth
– carbs), pepsin (stomach – protein) and bile (duodenum –
fats)
Stage 1: Ingestion – when food enters mouth
Stage 2: Digestion-begins in mouth. Mechanical - teeth and tongue creating bolus
(small pieces of food). Chemical – amylase breaks down bolus (
complex to simple carbs)
-food then moves to the pharynx (area where air tube meets
esophagus). Epiglottis covers airway tube when you swallow.
Food moves down the esophagus by peristalsis – muscle
contractions.
-food then moves to the stomach. Inside the stomach is gastric
juice - HCL, mucus (protects the stomach walls), and the enzyme
pepsin. Pepsin breaks down protein. 2 sphincters in the
stomach – one separates the esophagus from the stomach and
the other separates the small intestine from the stomach.
Digestion
Small Intestine chime from the stomach enters the small
intestine. It is 6m long and 2.5cm in diameter. The first meter of
it is called the Duodenum. The pancreas, liver, gall bladder
secrete into the duodenum. The liver produces Bile which
contains enzymes to break down fats.
Stage 3: Absorbing
This occurs in the small intestine. It has villi
to increase absorption of nutrients. It
expands the surface area of the small
intestine to 250 sq meters – size of a tennis
court!!!!
The large intestine is 5cm by 1.5m. Its job is
to absorb water
Bacteria: many live in the digestive system.
Ex: bacteria in the lg intestine produce
Vitamin K – blood clotting.
Stage 4: Eliminating
Undigested solid waste exits body via
the anus as feces.
Excretory system – removes liquids
and gases through the urinary tract.
Main organs – 2 kidneys, ureters,
bladder and urethra. Kidneys filter
blood and form urine