WAEC GCE 2019 - BIOLOGY ANSWER

+++++++++++++++++++++++++++
BIOLOGY OBJ
1-10: BACCCBBACA
11-20: BAABCBBBAA
21-30: ADDAAACDAA
31-40: BADADDBCBB
41-50: CBDACDCABA


+++++++++++++++++++++++++++

ANSWERS:


(1a)
Osmosis is defined as the flow of water or solvent molecules from a region of dilute or a weaker solution to a region of concentrated or stronger solution through a selectively or differentially permeable membrane

(1b)


(1bii)
The sugar solution in cavity of yam will remain the same. Therefore osmosis will not take place

(1biii)
Osmosis did not occur because the semi permeable membrane of yam cells was destroyed by boiling which did not allow movement of water into the solute (sugar) molecules

(1c)
(i) Potato
(ii) cocoyam

==========================

(2a)
TABULATE
Food substances|Two test reagents
Reducing sugar|Fehling's solution and benedict solution
Protein|Biuret solution and Million's solution
Fats and oil|Sudan(III) solution and

(2b)
TABULATE
Digestive enzyme|Location of production of enzyme|Site of action
Maltase|Small intestine(Ileum)|Walls of small intestine
Lipase|Duodenum|Liver
Sucrase|Small intestine(ileum)|Walls of small intestine
Amylase|Ileum or duodenum|Liver

(2ci)
Get a fresh leaf
-Wash in a clean water
-Boil in warm/hot water to soften it
-Put in alcohol to kill the cells and to remove the cholorophyll, thus the leaf is destarched

(2cii)
The starch is converted to simple sugars or simple carbohydrates|glucose

(2di)
To kill the protoplasm

(2dii)
To remove chlorophyll

(2diii)
To soften it

=========================

(3ai)
(i) Decomposition of the body.
(ii) Conversion of energy to trophic level
(iii) Release of nitrogenous compound to the soil

(3aii)
(i) It increases soil fertilty
(ii) It increases micro-organism activities such as nitrosomas and nitrobacter
(iii) It increases crop yield or production

(3aiii)
(i) Ammonia
(ii) Nitrogen
(iii) Carbondioxide

(3aiv)
Burning the dead dog and fumigating the affected areas

(3av)
To avoid epidemic outbreak of diseases

(3bi)
Fungi and protozoa

(3bii)
Goat and tiger

(3c)
(i)They breakdown dead or decomposing organisms
(ii)They use organic substrate to get their energy

(3d)
(i)They add fertility to the soil for plant growth
(ii)They indirectly support the balance of carbondioxide to oxygen in the air
(iii) They aerates the soil

=======================

(6a)
(i)Biennial Plant: This Is a flowering plant that takes two years to complete biological life cycle
(ii)Perenial Plant: This Is a plant that lives more than two years

(6b)
(i)Trap
(ii)Kill
(iii)Digestive prey
(iv)Absorb nutrient

(6c)
(i)Epigeal-Beans,Pumpkin
(ii)Hypogeal-Maize,coconut

(6d)
(i)Store water in the stem
(ii)To capture insect
(iii)To insect for pollination
(iv)For digging the soil for food
(v)To protect them for cold

(6e)
(i)Competition
(ii)Predation
(iii)Temperature

(6f)
(i)Conservation of energy
(ii)Energy can neither be created nor destroyed but can be transfered from one form to another

(6g)
(i) Hepatitis
(ii) Cirrhosis





+++++++++++++++++++++++++++
ANSWER LOADING......
+++++++++++++++++++++++++++