form 4 Biology chap6 pt6
-
Upload
cikgushaik -
Category
Education
-
view
1.382 -
download
3
description
Transcript of form 4 Biology chap6 pt6
![Page 1: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/1.jpg)
![Page 2: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/2.jpg)
LEARNING OUTCOME 1 Identify the part of the digestive system
where the formation of faeces takes place.
![Page 3: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/3.jpg)
LEARNING OUTCOME 2 Describe the formation of faeces.
• Undigested materials fibre (cellulose) + excretory product (bile pigments, dead cells) + bacteria + water enter colon (peristalsis)
• 90% of water + minerals are absorbed into the bloodstream faecal material becomes more solid = faeces.
![Page 4: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/4.jpg)
LEARNING OUTCOME 3 Explain the role of microorganisms in the
colon & the effect of antibiotics on them.
•Synthesis of vitamin B12 & vitamin K
•Conversion of cellulose to simple sugar
•B12 : formation of rbc•K : synthesis of blood clotting factors
![Page 5: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/5.jpg)
Overuse of antibiotics?
Reduce the good microbial population eg. E.Coli
![Page 6: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/6.jpg)
LEARNING OUTCOME 4 Explain defaecation & the importance of high fibre diets.
•Defaecation : the elimination of faeces from the body through the anus.
•Faeces is stored temporarily in rectum full sphincter muscles relax rectal wall contracts the faeces ejected via the anus.
![Page 7: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/7.jpg)
THE IMPORTANCE OF HIGH FIBRE DIETS.
The action of peristalsis is stimulated by fibres
A high fibre diet is very important for : Give bulk to the intestinal contents Helps to absorb water Prevent constipation
![Page 8: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/8.jpg)
LEARNING OUTCOME 5 What is the problem related to
defaecation?
•Constipation Haemorrhoids (piles) Colon cancer
![Page 9: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/9.jpg)
CONSTIPATION
The difficulty or infrequent evacuation of the bowels (elimination of faeces).
Faeces becomes dry & hard difficult to eliminate.
To prevent eat foods high in fibres, drinking more fluid
![Page 10: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/10.jpg)
HAEMORROIDS (PILES) Swollen veins in the
rectum or anus.
Constipation EXCESSIVE pressure exerted on the veins.
Itchiness, pain & rectal bleeding when the veins rupture.
![Page 11: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/11.jpg)
COLON CANCER Develops gradually.
A cell divides actively form a polyp malignant (month years later).
Symptoms : change in frequency of bowel movement, blood in faeces, abnominal pain, discomfort, weight loss.
Closely link to diet @ is hereditary.
Consume high-fibre & low fat diet.
![Page 12: form 4 Biology chap6 pt6](https://reader033.fdocuments.us/reader033/viewer/2022042606/54858797b4af9f24368b45da/html5/thumbnails/12.jpg)