2017 - JAMB Biology Past Questions and Answers - page 4
31
The structure is adapted for
A
omnivores
B
herbivores
C
canivores
D
omnivores and canivore
correct option: a
Users' Answers & Comments32
The product after the union of the male and female gamete in animals is called
A
sperm
B
egg
C
embryo
D
zygote
correct option: d
Human fertilization is the union of a human egg and sperm, usually occurring in the ampulla of the fallopian tube.
The result of this union is the production of a zygote cell, or fertilized egg, initiating prenatal development.
Users' Answers & CommentsThe result of this union is the production of a zygote cell, or fertilized egg, initiating prenatal development.
33
The possession of scales, laying of eggs with shells and bony structure of the head are characteristics shared by
A
birds and reptiles
B
fishes and birds
C
reptiles and fishes
D
birds and molluscs
correct option: a
Its long been recognized that birds and reptiles share many characteristics:
Both have skulls that abut the first neck vertebra with a single ball-and-socket joint.
Both birds and reptiles excrete nitrogenous wastes as uric acid; mammals excrete urea, fish ammonia.
Both lay similar highly yolked eggs
Bird feather is homologous to the reptile scale. Both develop from an epidermal elevation over a nourishing dermal core. Scales flatten, feather buds roll into a cylinder shaped tube
Users' Answers & CommentsBoth have skulls that abut the first neck vertebra with a single ball-and-socket joint.
Both birds and reptiles excrete nitrogenous wastes as uric acid; mammals excrete urea, fish ammonia.
Both lay similar highly yolked eggs
Bird feather is homologous to the reptile scale. Both develop from an epidermal elevation over a nourishing dermal core. Scales flatten, feather buds roll into a cylinder shaped tube
34
The lungs of the lung fish is an adaptation for respiration _______?
A
to complement gills while in water
B
to complement gills while on land
C
while on land
D
while in water
correct option: d
Lungfish are best known for retaining the ability to breathe air, to survive drought
Users' Answers & Comments35
Which of the following is an example of active transport?
A
Oxygen exchanging between red blood cells and liver cells
B
Carbon dioxide exchanging between muscle cells and red blood cells
C
Water moving out of the small intestine
D
Sodium being reabsorbed in the kidney
correct option: a
Although sodium ions are small, their charge prevents them from moving across the cell membrane through simple diffusion. They must be transported using active transport.
Users' Answers & Comments36
The key event in the transition of the amphibians from water to land is the ________
A
replacement of the gills with lungs
B
possession of webbed limbs
C
limbs
D
possession of tympanic membrane
correct option: a
Amphibians display some interesting and changing characteristics as they metamorphose through various forms on their way to adulthood. The frog, for instance, begins life underwater as a larva with gills and becomes and air-breather with lungs as an adult.
&therefore4; in case of draught, frog can amphibians can use lungs to breathe on land
Users' Answers & Comments&therefore4; in case of draught, frog can amphibians can use lungs to breathe on land
37
Erythrocytes are known as ________
A
white blood cell
B
red blood cells
C
phagocytes
D
leucocytes
correct option: b
A red blood cell(erthyrocytes), which (in humans) is typically a biconcave disc without a nucleus.
Erythrocytes contain the pigment haemoglobin, which imparts the red colour to blood, and transport oxygen and carbon dioxide to and from the tissues.
Users' Answers & CommentsErythrocytes contain the pigment haemoglobin, which imparts the red colour to blood, and transport oxygen and carbon dioxide to and from the tissues.
38
Gregor Mendel is regarded as the father of ______
A
variation
B
genetics
C
mycology
D
natural selection
correct option: b
Gregor Mendel, through his work on pea plants, discovered the fundamental laws of inheritance.
He deduced that genes come in pairs and are inherited as distinct units, one from each parent. Mendel tracked the segregation of parental genes and their appearance in the offspring as dominant or recessive traits.
Users' Answers & CommentsHe deduced that genes come in pairs and are inherited as distinct units, one from each parent. Mendel tracked the segregation of parental genes and their appearance in the offspring as dominant or recessive traits.
39
The most efficient respiratory structure used by free living protozoan is ________
A
body surface
B
gills
C
buccal cavity
D
spiracle
correct option: a
Protozoa do not have any organellae for the process of respiration. The limiting permeable membrane (body surface) acts as a respiratory surface.
The free molecular oxy¬gen from the surrounding media enters into the body by diffusion. Presence of a cyto¬chrome system has been demonstrated in protozoa.
Users' Answers & CommentsThe free molecular oxy¬gen from the surrounding media enters into the body by diffusion. Presence of a cyto¬chrome system has been demonstrated in protozoa.
40
Carbon (iv) oxide is added to the atmosphere when ________?
A
plants build-up organic compounds
B
plants absorb mineral salts
C
sugars are completely broken down in animals
D
there is thunderstorm
correct option: a
Plant build of of organic compounds such as oil, coal and gas is a great source of emission of carbon dioxide into the atmosphere
Human activities such as the burning of oil, coal and gas, as well as deforestation are the primary cause of the increased carbon dioxide concentrations in the atmosphere.
Other source such has respiration by animals, thunderstorm release carbon dioxide in smaller quantities compare to 87% of carbon dioxide emission from plants build-up organic compounds through human activities
Users' Answers & CommentsHuman activities such as the burning of oil, coal and gas, as well as deforestation are the primary cause of the increased carbon dioxide concentrations in the atmosphere.
Other source such has respiration by animals, thunderstorm release carbon dioxide in smaller quantities compare to 87% of carbon dioxide emission from plants build-up organic compounds through human activities