Digestive and excretory systems

1. The Digestive System
Life Science 5
8/08

2. The digestive system is
a group of organs that
process the food we eat
and takes out the
nutrients our bodies need.

3. It all begins in the mouth where food
is broken into small pieces by the
teeth and mixed with saliva (spit)
which has chemicals that help with
digestion.

4. After food is chewed up and mixed with
saliva it moves down a tube called the
esophagus.

5. The esophagus delivers the food to a
storage bag, the stomach where it is
mixed with other chemicals and
digestive juices.

6. Bile is an important digestive juice
that is made in the liver.

7. After it leaves
the stomach
the material
moves into a
long, folded
small
intestine
where the
nutrients are
removed.

8. The inside of the small intestine is
lined with millions of tiny, finger-like
projections called villi (vil eye).
Villi
absorb
nutrients
from our
food.
Villi is the plural
for villus.
1 villus
2 villi

9. After the nutrients have been removed
the watery material moves into the
large intestine, also called the colon.
The large intestine is
shorter but bigger around
than the small intestine.
Stomach
Small
intestine
Large
intestine

10. Most of the liquid is removed from the
used-up food material in a healthy
person’s large intestine.

After that
the solid
waste goes
into the
toilet.

11. Let’s review:
After it leaves the mouth
the order of the organs that
food passes through is

12. Let’s review:
After it leaves the mouth
the order of the organs that
food passes through is
1. Esophagus

13. Let’s review:
After it leaves the mouth
the order of the organs that
food passes through is
1. Esophagus
2. Stomach

14. Let’s review:
After it leaves the mouth
the order of the organs that
food passes through is
1. Esophagus
2. Stomach
3. Small intestine

15. Let’s review:
After it leaves the mouth
the order of the organs that
food passes through is
1. Esophagus
2. Stomach
3. Small intestine
4. Large intestine

17. 1

18. 1
2

19. 1
2
3

20. 1
2
3
4

22. Excretory system

23. The excretory system
removes cellular waste
from the blood.

24. The excretory system
removes cellular waste
from the blood.
It’s often called the urinary system
because urine is how the waste leaves
the body.

25. The main organs in the excretory
system are the kidneys.

26. Every living animal cell creates waste
called urea as it uses energy. This
waste is carried away in the blood.

27. Blood flows through the kidneys
where urea is removed.

28. Urea is removed through tiny tubes in
the kidneys called nephrons.

29. Urea and other
waste products
are sent from the
kidneys as urine
(a yellow liquid)
in tubes called
jjjjjjjjjjjjureters,
or urine tubes.

30. The ureters
take urine to a
bag-like
muscle called
the bladder
where it is
stored until we
go to the
bathroom.

31. The excretory
system

32. Let’s review:
What is the tube that carries food
from the mouth to the stomach?

33. Let’s review:
What is the tube that carries food
from the mouth to the stomach?
The esophagus

34. Let’s review:
What is the tube that carries food
from the mouth to the stomach?
The esophagus

35. Let’s review:
Where does food go after it leaves
the stomach?

36. Let’s review:
Where does food go after it leaves
the stomach?
Small intestine

37. Let’s review:
Where does food go after it leaves
the stomach?
Small intestine

38. Let’s review:
Where is most water removed
from food material before it leaves
the body?

39. Let’s review:
Where is most water removed
from food material before it leaves
the body?
Large intestine
also called the
colon

40. Let’s review:
Where is most water removed
from food material before it leaves
the body?
Large intestine
also called the
colon

41. Let’s review:
Where are nutrients removed from
food?

42. Let’s review:
Where are nutrients removed from
food?
Small intestine

43. Let’s review:
Where are nutrients removed from
food?
Small intestine
The villi

44. Let’s review:
What are two examples of
digestive juices?

45. Let’s review:
What are two examples of
digestive juices?
Saliva
from
the mouth

46. Let’s review:
What are two examples of
digestive juices?
Saliva
from
the mouth

47. Let’s review:
What are two examples of
digestive juices?
Saliva
from
the mouth
Bile
from the
liver

48. Let’s review:
What are two examples of
digestive juices?
Saliva
from
the mouth
Bile
from the
liver

49. Let’s review:
What are the most important organs
in the excretory system?

50. Let’s review:
What are the most important organs
in the excretory system?
The kidneys

51. Let’s review:
What are the most important organs
in the excretory system?
The kidneys

52. Let’s review:
What do the kidneys do?

53. Let’s review:
What do the kidneys do?
They remove
cellular waste
(urea) from the
blood.

54. Let’s review:
What do the kidneys do?
They remove
cellular waste
(urea) from the
blood.

55. Let’s review:
What happens to the waste after the
kidneys remove it from the blood?

56. Let’s review:
What happens to the waste after the
kidneys remove it from the blood?
It goes
as urine
to the
bladder.

57. Let’s review:
What happens to the waste after the
kidneys remove it from the blood?
It goes
as urine
to the
bladder.