Transcript What is the Digestive System?

New Unit!! 
 There are four columns :
 What I Know
 What I Want to Learn
 How I Will Learn More
 What I Have Learned
 Complete the first three columns now.
 Hand it in!
 Groups of organs with specific structures and
functions work together as systems, which interact
with other systems in the body.
 The development and uses of technology to
maintain human health are based, in part, on the
changing needs of society.
 With a partner, you will be attempting to match up the
organ system with its respective major organs and
major functions.
 Cut out the rectangles and arrange them on the piece
of construction paper so that organ systems, major
organs, and major functions are grouped together
 Once you are as sure as you’re going to be about all
your matches being correct, glue them all down to the
piece of construction paper!!
 We will then take this up as a class.
Organ system
Major organs
Major functions
Integumentary
Skin, hair, nails, glands
Covers and protects body, glands
help control body temperature
Skeletal
Bones, cartilage
Supports and protects body, allows
movement
Muscular
Skeletal, smooth, and cardiac
muscle, tendons, ligaments
Provides movement
Digestive
Mouth, esophagus, stomach,
pancreas, gall bladder, liver,
intestines, rectum
Ingestion, digestion, absorption of
nutrients, elimination of solid
wastes
Respiratory
Nose, mouth, trachea, lungs,
bronchi, bronchioles, alveoli,
diaphragm
Exchange of gases
Circulatory
Heart, blood vessels, blood
Transportation of materials
(oxygen, wastes, nutrients)
Nervous
Brain, nerves, spinal cord
Controls and coordinates body
functions
Endocrine
Pituitary gland, pancreas, ovaries,
testes
Controls growth, development, and
metabolism
Excretory
Skin, kidney, bladder, ureter,
urethra
Elimination of wastes
Reproductive
Ovaries, fallopian tubes, vagina, vas
deferens, penis
Reproduction
Lymphatic
White blood cells, thymus, spleen,
lymph nodes
Protects body from disease,
circulates lymph fluid, absorbs and
 Who got at least 5 out of 22 correct?
 Who got at least 10 out of 22 correct?
 Who got at least 15 out of 22 correct?
 Who has never seen this before????
 Even if you’ve never seen it before, don’t worry about it
– it’s the change in the curriculum that’s done it!!
 We will be focussing on the Digestive, Respiratory, and
Circulatory Systems in this unit – that’s it!!
 It’s going to be wonderful 
 In the last unit (biodiversity if you’ve already
forgotten), we looked at different kingdoms, and more
specifically, the phylums of kingdom Animalia
 We saw that in the simpler phylum of Porifera, those
organisms did not have specialized structures and
tissues, unlike in later phylums, such as Chordata
 In this unit, we will explore how groups of organs with
specific structures and functions work together as
systems, which interact with other systems of the body
Organism
Organ System
Organ
Tissue
Cell
Molecule
Atom
 ORGAN SYSTEM
This is a group of different organs that work together
to perform a common task
 ORGAN
This is a group of tissues that work together to
perform a common task
 TISSUE
This is a group of cells that work together to perform a
common task
What is the Digestive System?
 The digestive system is a long, muscular tube
 The inner surface of this tube is called the lumen and
it is continuous with the outside of the body
 The entire system is approximately 9m in length and is
usually a one way tract
Why do we need a digestive system?
 Our body cannot readily use food in the form it comes
in – some foods are too large and not water soluble
 The digestive system breaks down the food we eat into
small pieces that can be metabolized by individual
cells in our body
GLUCOSE + 6H2O  6CO2 + 6H2O + 36ATP
 ATP is the form of energy out body can use to perform
everyday functions
 We must eat food that contain nutrients (carbs, lipids,
proteins, vitamins, minerals, H2O) in order for our
body to function and provide us with the energy we
need
 We need to break down those large molecules into smaller
ones so that they may be used by cells (ex: nutrients)
 There are four stages:
1. Ingestion: taking in food
2. Digestion: breaking down of food by enzymes
1. Mechanical
2. Chemical
3. Absorption: nutrients enter our blood stream through the
small intestines to our body’s cells
4. Egestion: discharging of wastes
 Through the alimentary canal
 “tube-within-a-tube”
 This tract allows digestive processes to be separated
into different regions, the regions being:
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Mouth
Pharynx
Esophagus
Stomach
Small intestine
Large intestine
Rectum
Anus
 Anyone remember where we’ve seen enzymes before?
 Enzymes are proteins that breakdown complex
molecules
 They have an optimum pH and temperature
 Humans: 37ºC
 pH levels
 Pepsin in stomach has an optimum pH 2-3
 Amylase in mouth has an optimum pH 7
 Trypsin in small intestine has an optimum pH 9-10
 Digestion Overview:
 http://www.youtube.com/watch?v=I-yu6WSdpVQ
 The Digestive System...and YOU!
 http://www.youtube.com/watch?v=cWhLXdopQYo&feature=
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