JAMB - Biology (2021)

• 1

  One of the functions of the xylem is?

  Απάντηση

  (A)

  strengthening the stem
• 2

  Which of the statements below is not characteristic of wind-pollinated flowers?

  Απάντηση

  (C)

  The pollen grains have rough spiny surfaces
• 3

  Some of the features of an animal are scales, teeth, nares, and backbone. The animal is likely to be a?

  Απάντηση

  (C)

  lizard
• 4

  Choose the sequence which represents the correct order of organisms in a food chain

  Απάντηση

  (B)

  Grass, grasshopper, toad, snake, hawk
• 5

  Flatworms and roundworms are said to be invertebrates because?

  Απάντηση

  (D)

  they have no backbones
• 6

  When a Spirogyra cell is immersed in a salt solution more concentrated than its cell sap, it?

  Απάντηση

  (D)

  loses water and shrivels
• 7

  Which of the following is NOT regarded as a pollutant on land or in the air?

  Απάντηση

  (B)

  Nitrogen
• 8

  The initial volume of water poured into a bag of dry soil was 50ml and the amount that drained through was 35mI. The percentage water content of the fully soaked soil is therefore?

  Απάντηση

  (D)

  30.0
• 9

  When the original king and queen of termites die, they are replaced by 

  Απάντηση

  (D)

  developing nymphs nurtured as secondary reproductives
• 10

  In demonstrating the importance of mineral elements in plants, the culture bottle must be darkened to?

  Απάντηση

  (A)

  prevent algal growth in culture solution
• 11

  In the mammalian respiratory system. exchange of gases occurs in the?

  Απάντηση

  (D)

  alveoli
• 12

  Aged erythrocytes are destroyed in the?

  Απάντηση

  (B)

  liver
• 13

  The villus in the small intestine is significant because it?

  Απάντηση

  (A)

  increases the surface area for absorption
• 14

  Which of the following food substances will produce a brick-red colour when warmed with Benedict's solution?

  Απάντηση

  (A)

  Glucose
• 15

  The blood vessel which carries blood from the alimentary canal to the liver is the?

  Απάντηση

  (C)

  hepatic portal vein
• 16

  Which of the following is TRUE of the process of conjugation in Paramecium?

  Απάντηση

  (D)

  Each micronucleus divides twice
• 17

  People who suck petrol with their mouths run the risk of increasing in their blood the concentration of

  Απάντηση

  (B)

  lead
• 18

  Which of the following is a measure for the control of bilharzia?

  Απάντηση

  (B)

  Application of molluscicides in water bodies
• 19

  The appendicular skeleton is composed of the pectoral girdle?

  Απάντηση

  (A)

  pelvic girdle, fore and hind limbs
• 20

  A freshwater plant such as water lily can solve the problem of buoyancy by the possession of?

  Απάντηση

  (A)

  aerenchyma tissues
• 21

  The correct sequence for the perception of smell in mammals is?

  Απάντηση

  (D)

  dissolved chemicals --> sensory cells --> olfactory nerve --> brain
• 22

  I. High birth rate and high immigration rate

  II. Low birth rate and high immigration rate

  III. Low mortality rate and low emigration rate

  IV. High mortality rate and high emigration rate.

  Which combination of the above can cause rapid over-crowding in climax biotic communities and human settlements? 

  Απάντηση

  (B)

  I and III
• 23

  The number of plant species obtained from a population study of a garden is as follows: Guinea grass (15), Ipomoea spp (5), Sida spp (7) and Imperata spp (23)

  What is the percentage of occurrence of Imperata spp?

  Απάντηση

  (C)

  46%
• 24

  When a marine fish was taken from the ocean and put in a tank of fresh water, it died after a short period because? 

  Απάντηση

  (B)

  the body cells of the fish swelled and burst as a result of the hypotonic fresh water
• 25

  If a DNA strand has a base sequence TCA, its complementary strand must be?

  Απάντηση

  (D)

  AGT
• 26

  The two key cations involved in the action potential of nervous transmissions are?

  Απάντηση

  (C)

  Na+ and K+
• 27

  I. Rattus rattus. Il. Agama agama III. Bufo regularis IV. Tilapia zillii
  The order of evolutionary advancement of the above vertebrates is?

  Απάντηση

  (D)

  IV, III, II, I
• 28

  Which of the following produces both hormones and enzymes?

  Απάντηση

  (B)

  Pancreas
• 29

  The correct sequence of the movement of urea during urine formation is?

  Απάντηση

  (B)

  glomerulus -> Bowman's capsule -> convoluted tubule -> Henle's loop -> convoluted tubule -> collecting tubule
• 30

  The order of passage of food in the digestive system is

  Απάντηση

  (A)

  ileum --> caecum ->large intestine -> rectum
• 31

  Mass of a crucible = 10g,

  Mass of a crucible and soil before heating =29g

  Mass of a crucible and soil after heating = 18g

  From the information above, determine the percentage of water in the given soil sample?

  Απάντηση

  (D)

  60%
• 32

  I. Stomata --> Spirogyra

  II. Alveoli --> Earthworm

  III. Malpighian tubule -> Mammal

  IV. Contractile vacuole -> Protozoa

  Which of the above structures is correctly matched with the organisms in which it is found?

  Απάντηση

  (C)

  IV
• 33

  The sequence of the one-way gaseous exchange mechanism in a fish is?

  Απάντηση

  (B)

  mouth -> gills > operculum
• 34

  Which of the following is true in blood transfusion?

  Απάντηση

  (A)

  A person of blood group AB can donate blood only to another person of blood group AB
• 35

  The plants that grow in deserts or very dry areas are referred to as?

  Απάντηση

  (C)

  xerophytes