WAEC SSCE - Biology - 1997
Question 1 Report
Crops grown mainly to feed animals are called
Answer Details
Crops grown mainly to feed animals are called "forage crops". Forage crops are plants that are grown to provide forage for livestock. They are rich in nutrients and are used to feed animals like cows, sheep, goats, horses, and others. Some examples of forage crops include alfalfa, clover, grasses, and other legumes. These crops are usually harvested when they are young and tender, before they have a chance to produce seeds, and are fed to animals either fresh or dried.
Question 2 Report
The essential parts of a flower are
Answer Details
The essential parts of a flower are the androecium and gynoecium. The androecium is the male reproductive part of the flower, which includes the anther and filament. The anther is the part of the flower that produces pollen, and the filament supports the anther. The gynoecium is the female reproductive part of the flower, which includes the stigma and style. The stigma is the part of the flower where pollen lands, and the style connects the stigma to the ovary. The ovary contains the ovules, which develop into seeds after fertilization. While petals and sepals may play important roles in attracting pollinators and protecting the flower, they are not considered essential for the reproduction of the plant.
Question 3 Report
Northern Guinea savanna is associated with
Answer Details
Northern Guinea savanna is associated with abundant grasses. The Northern Guinea savanna is a vegetation zone that stretches across West Africa, including countries such as Nigeria, Ghana, and Cameroon. The zone is characterized by tall grasses and a few scattered trees, shrubs, and small plants. It is also known for its relatively dry climate with a rainy season that lasts for about six months. The abundance of grasses in the Northern Guinea savanna makes it ideal for grazing animals such as cattle, sheep, and goats.
Question 4 Report
In an inter-species competition, the less successful species usually
Answer Details
In an inter-species competition, the less successful species usually become eliminated. Inter-species competition refers to a type of competition where two or more species are competing for the same resources such as food, water, and shelter. In this type of competition, the species that is better adapted to the environment and can utilize the resources more efficiently has a competitive edge over the other species. As a result, the less successful species usually cannot acquire enough resources to survive and reproduce, leading to their elimination. Therefore, becoming eliminated is the most likely outcome for the less successful species in inter-species competition.
Question 5 Report
The maximum and minimum thermometer is used to measure
Answer Details
The maximum and minimum thermometer is used to measure the highest and lowest temperature of the day. This thermometer consists of a U-shaped glass tube filled with alcohol or mercury. The liquid in the thermometer expands when heated and contracts when cooled, causing it to move up or down the tube. At one end of the thermometer, there is a small bulb containing alcohol or mercury, and at the other end, there is a constriction in the tube. The constriction prevents the liquid from flowing back to the bulb when it contracts due to cooling. The thermometer is designed in a way that the liquid moves to indicate the highest temperature reached during the day, and the lowest temperature reached during the night. The thermometer is reset every day to record new maximum and minimum temperatures. This information can be used to determine the temperature range for a given day, which is useful in understanding the local weather patterns. Therefore, the correct option is "highest and lowest temperature of the day". It is important to note that this type of thermometer is not used to measure light intensity, atmospheric pressure, rainfall, or soil temperature.
Question 6 Report
Which of the following is an abiotic factor?
Answer Details
An abiotic factor refers to the non-living components of an ecosystem that affect living organisms, such as temperature, water, sunlight, soil, etc. Based on this definition, the abiotic factor among the options given is "Rainfall." It is a non-living component of the environment and an important abiotic factor that affects various aspects of an ecosystem, including the growth and survival of plants and animals. Rainfall provides the necessary water for plants to grow and for animals to drink, and it affects the distribution of species and the productivity of ecosystems.
Question 8 Report
The eye defect represented in the diagram is
Question 10 Report
Which of the following is an example of a reflex action?
Answer Details
An example of a reflex action is sneezing. When an irritant enters the nasal passage, the receptors in the nose send a signal to the brain which then sends a message to the muscles in the chest, throat, and face to quickly expel air, removing the irritant. This action is automatic and involuntary, occurring without conscious thought or effort. Biting, dancing, singing, and talking are not reflex actions as they involve more complex movements and cognitive processing.
Question 11 Report
What will be the colour of the solution in the test tube labelled II at
the end of the experiment?
Answer Details
Question 12 Report
Clotting of blood is a function of
Answer Details
Clotting of blood is a complex process that involves the formation of a blood clot to stop bleeding after injury. One of the important factors in this process is vitamin K, which is essential for the production of certain proteins that are needed for blood clotting. When there is an injury or damage to a blood vessel, platelets in the blood begin to clump together and form a plug at the site of injury. This plug is then reinforced by a network of proteins called fibrin, which are produced by a series of chemical reactions known as the coagulation cascade. Vitamin K is necessary for the production of several of the proteins involved in the coagulation cascade, including prothrombin and factors VII, IX, and X. These proteins require vitamin K for a process called carboxylation, which is necessary for their activation and function in the coagulation cascade. Without sufficient vitamin K, the coagulation cascade cannot function properly, leading to an increased risk of bleeding and bruising. So, vitamin K is essential for the proper clotting of blood.
Question 13 Report
In which of the following is the knowledge of genetics not applicable?
Answer Details
Question 16 Report
Which of the following organisms is viviparous?
Answer Details
Sheep is the organism that is viviparous. Viviparity is a mode of reproduction where the embryo develops inside the mother's body and is nourished through a placenta or a similar structure, and the offspring are born alive. Sheep are mammals and, like other mammals, give birth to live young ones that have been nourished inside the mother's body through a placenta. The other organisms listed are not viviparous, as tapeworms, snails, and grasshoppers are oviparous, meaning they lay eggs, and lizards are oviparous or ovoviviparous, meaning they lay eggs or retain the eggs inside their body until they are ready to hatch.
Question 17 Report
Which of the following hind limb bones is equivalent to the humerus of the forelimb?
Answer Details
The femur is the hind limb bone that is equivalent to the humerus of the forelimb. The humerus is the long bone in the upper arm of mammals that connects the shoulder to the elbow. In the hind limb of mammals, the femur is the long bone that connects the hip to the knee. The femur and the humerus have a similar structure and function, as they are both weight-bearing bones that support the body and allow for movement. They also have similar shapes, with rounded heads that fit into sockets to form joints. In contrast, the other hind limb bones listed - patella, tarsal, tibia, and fibula - have different shapes and functions compared to the humerus. The patella is the kneecap, a small, triangular bone that sits in front of the knee joint and helps to protect the joint and increase the leverage of the thigh muscles. The tarsal bones are a group of seven bones in the ankle that help to support the foot and enable movement. The tibia and fibula are the two long bones in the lower leg that connect the knee to the ankle. The tibia is the larger and stronger of the two, and is the main weight-bearing bone in the lower leg. The fibula is a thinner bone that runs alongside the tibia and helps to provide support and stability to the ankle joint. Therefore, the femur is the hind limb bone that is equivalent to the humerus of the forelimb, as they have a similar structure, function, and shape.
Question 18 Report
Which of the following organism possesses both plant and animal characteristics?
Answer Details
Among the options given, Euglena is an organism that possesses both plant and animal characteristics. Euglena is a single-celled organism that can perform photosynthesis using chloroplasts, just like a plant, to produce its own food. It also has a unique structure called an eyespot that allows it to detect light and move towards it, much like how an animal would do. In addition to that, Euglena can also obtain its nutrition by ingesting other small organisms, making it a mixotroph, which means it can obtain nutrients from both autotrophic (producing own food) and heterotrophic (consuming other organisms) methods. Hence, Euglena is an excellent example of an organism that has characteristics of both plant and animal.
Question 21 Report
In which of the underlisted blood groupings is agglutination likely to occur during transfusion?
Answer Details
Question 22 Report
Which of the following factors may not cause over-crowding?
Answer Details
Only reduced birth rate may not cause over-crowding. Over-crowding occurs when there are too many individuals in a given space, leading to competition for resources such as food, water, and shelter. Limited space, scarcity of food, increased birth rate, and loose immigration conditions are all factors that can lead to over-crowding by increasing the number of individuals in a given area. However, reduced birth rate decreases the number of individuals in the area and can help to alleviate over-crowding.
Question 23 Report
In which of these forms is carbohydrate stored in yam?
Answer Details
Carbohydrates in yam are primarily stored in the form of starch. Starch is a complex carbohydrate that is made up of long chains of glucose molecules. When yams photosynthesize, they convert the energy from sunlight into glucose, which they then store as starch in their underground tubers. Starch is an excellent storage molecule because it can be broken down into glucose when energy is needed. This allows yams to survive periods of low sunlight and water by using their stored starch for energy. The other carbohydrate options listed - glucose, maltose, glycogen, and cellulose - are not typically stored in yams. Glucose is a simple sugar that is used for energy production in cells. Maltose is a disaccharide made up of two glucose molecules and is found in grains and some vegetables, but not typically in yams. Glycogen is a complex carbohydrate that is similar to starch, but it is primarily stored in animals rather than plants. Finally, cellulose is a structural carbohydrate found in plant cell walls, and it is not typically used for energy storage.
Question 25 Report
Which of the following is the correct sequence for energy transfer and nutrient cycling among living things
in an ecosystem?
Answer Details
The correct sequence for energy transfer and nutrient cycling among living things in an ecosystem is: Producers → consumers → decomposers Producers are organisms that produce their own food through photosynthesis or chemosynthesis. They are the base of the food chain and transfer energy to the consumers (herbivores, carnivores, and omnivores) when they are consumed. The consumers, in turn, pass on the energy to the decomposers, which break down the dead organic matter and return nutrients to the soil, completing the nutrient cycle. Therefore, the correct sequence is producers → consumers → decomposers.
Question 26 Report
Which of the following organisms will have the highest biomass?