General Biology I — 2026-exam Past Questions

University of Ilorin BIO101: 197 questions.

Topics: Cell structure and organisation, Chromosomes, genes, their relationships and importance, Interrelationships of organisms, General reproduction, Characteristics and classification of living things, Functions of cellular organelles, Elements of ecology and types of habitat, Heredity and evolution, Living things, Characteristics and Reproduction

1. A plant cell placed in a hypertonic solution becomes?
   1. Turgid
   2. Flaccid
   3. Plasmolysed
   4. Deplasmolysed
2. Cristae in mitochondria function to?
   1. Store DNA
   2. Increase surface area
   3. Trap light energy
   4. Digest substrates
3. Which of the following best explains why cells remain microscopic in size?
   1. Increase in metabolic rate
   2. Increase in surface area relative to volume
   3. Decrease in surface area to volume ratio
   4. Presence of organelles
4. A cell that lacks a rigid cell wall is:
   1. Fungal cell
   2. Bacterial cell
   3. Animal cell
   4. Plant cell
5. Who coined the word chromosome?
   1. Sutton
   2. Boveri
   3. Waldeyer
   4. Darwin
6. Which of these groups makes up the majority of saprophytes?
   1. Bacteria
   2. Fungi
   3. Monera
   4. Protozoa
7. What type of association is found in an epiphytic orchid on a tree?
   1. Commensalism
   2. Mutualism
   3. Parasitism
   4. Competition
8. The structure that forms a long thread with beads is?
   1. Chromatin
   2. Cytoplasm
   3. Nucleolus
   4. Centriole
9. Which of the following are the essential parts of a flower?
   1. Petals and sepals
   2. Stamens and carpels
   3. Receptacle and stalk
   4. Corolla and calyx
10. A test cross involves crossing an organism with a?
    1. Homozygous dominant phenotype
    2. Heterozygous phenotype
    3. Homozygous recessive phenotype
    4. Dominant F₁ hybrid
11. A ripened ovary is known as a?
    1. Seed
    2. Fruit
    3. Ovule
    4. Carpel
12. The phenotypic ratio of the F₂ generation in a monohybrid cross is?
    1. 1:2:1
    2. 3:1
    3. 9:3:3:1
    4. 2:1
13. Reproduction in man includes all of the following except?
    1. Gametogenesis
    2. Parthenocarpy
    3. Fertilization
    4. Implantation
14. Which principle is a core tenet of Lamarckism?
    1. Natural selection
    2. Inheritance of acquired traits
    3. Survival of the fittest
    4. Genetic mutation
15. What percentage of energy is typically transferred to each subsequent trophic level?
    1. 1%
    2. 5%
    3. 100%
    4. 10%
16. Tonoplast is the membrane associated with which organelle?
    1. Mitochondrion
    2. Nucleus
    3. Chloroplast
    4. Large central vacuole
17. The surface area to volume (SA/V) ratio decreases when the cell?
    1. Divides
    2. Enlarges
    3. Shrinks
    4. Flattens
18. A lion and a hyena preying on the same organism can be described as?
    1. Parasitism
    2. Mutualism
    3. Competition
    4. Commensalism
19. A plant cell that has had its cell wall removed is known as a?
    1. Apoplast
    2. Protoplast
    3. Symplast
    4. Chloroplast
20. Lamarck's theory of evolution is best described as the?
    1. Theory of natural selection
    2. Theory of use and disuse
    3. Theory of genetic mutation
    4. Theory of punctuated equilibrium
21. Which phenomenon refutes Lamarck's theory of evolution?
    1. The long necks of modern giraffes
    2. Vestigial organs in whales
    3. Developed muscles of a bodybuilder are not inherited by offspring
    4. Resistance of bacteria to antibiotics
22. According to Lamarckism, how did giraffes develop long necks?
    1. Random mutations occurred in the population
    2. They stretched their necks for food and passed the trait to offspring
    3. Short-necked giraffes died out due to starvation
    4. Predation favored those with better visibility
23. Who among the following did not contribute to the Cell Theory?
    1. Matthias Schleiden
    2. Robert Hooke
    3. Theodor Schwann
    4. Rudolf Virchow
24. What relationship exists between bacteria and a dead log of wood?
    1. Parasitism
    2. Saprotrophism
    3. Commensalism
    4. Mutualism
25. A rainforest and its physical properties, such as climate and rainfall, is an example of?
    1. Population
    2. Community
    3. Ecosystem
    4. Biosphere
26. What is the primary benefit sea anemones receive from hermit crabs?
    1. Transportation to feeding areas
    2. Defense against predators
    3. Protection from dehydration
    4. Access to oxygenated water
27. The relationship between sea anemones and clownfish is?
    1. Commensalism
    2. Symbiosis
    3. Mutualism
    4. Predation
28. How do eukaryotes overcome the limits of diffusion?
    1. Increasing cell size
    2. Compartmentalization
    3. Reducing metabolic rate
    4. Eliminating the cytoplasm
29. The type of commensalism where mites use larger insects for transport is?
    1. Inquilinism
    2. Metabiosis
    3. Phoresy
    4. Mutualism
30. Which chromosome is responsible for carrying the gene for colour blindness in males?
    1. Y chromosome
    2. X chromosome
    3. Both X and Y chromosomes
    4. Either X or Y chromosome
31. Columnar epithelial cells are primarily adapted for:
    1. Absorption and secretion
    2. Fast movement
    3. Physical protection
    4. Rapid diffusion
32. Temperature and soil represent which level of an ecosystem?
    1. Species
    2. Population
    3. Community
    4. Abiotic environment
33. The first Taxonomist to provide a logical system for naming and classifying organisms was?
    1. Aristotle
    2. Waldeyer
    3. Carl Von Linnaeus
    4. John Dalton
34. Which of the following was not part of the unified cell theory proposed by Schleiden and Schwann?
    1. All living things are composed of one or more cells
    2. The cell is the basic unit of life
    3. New cells arise from pre-existing cells
    4. Cells contain hereditary information
35. Which cell organelle is responsible for intracellular transportation and secretion?
    1. Lysosome
    2. Golgi apparatus
    3. Microbodies
    4. Endoplasmic reticulum
36. Which cell is adapted for the transmission of electrical signals in animals?
    1. Epithelial cell
    2. Neuron
    3. Somatic cell
    4. Muscle cell
37. How many whorls must a flower have to be considered complete?
    1. 3
    2. 4
    3. 5
    4. 6
38. What did Antonie van Leeuwenhoek first observe using his microscope?
    1. Viruses
    2. Bacteria
    3. Animalcules
    4. Tissues
39. Which organelle is commonly known as the suicidal bag of the cell?
    1. Mitochondrion
    2. Ribosome
    3. Lysosome
    4. Nucleus
40. During which stage of mitosis do sister chromatids separate?
    1. Metaphase
    2. Anaphase
    3. Interphase
    4. Prophase
41. The ecological relationship in which an organism lives in the permanent habitat of another is?
    1. Inquilinism
    2. Metabiosis
    3. None of these
    4. Phoresy
42. Chromosomes are uncondensed at what stage of the cell cycle?
    1. Prophase
    2. Interphase
    3. Anaphase
    4. Telophase
43. What facilitates adhesion between cell organelles and the cytoskeleton?
    1. Cytoplasmic streaming
    2. Microfilaments
    3. Peripheral proteins
    4. Microtubules
44. Which of the following is an example of parasitism?
    1. Clownfish and sea anemone
    2. Barnacle and whale
    3. Tapeworm in the human intestine
    4. Remora attached to a shark
45. To decrease the surface area to volume ratio of a cell, its shape should be:
    1. Spherical
    2. Cuboidal
    3. Flattened
    4. Elongated
46. If a classification system in a classroom is to be established, which of these steps is typically not taken?
    1. Listing of the animals
    2. Collection of the animals
    3. Comparison according to characteristics
    4. Observation of behaviour
47. Which of the following is not part of the cell theory?
    1. Cells originate spontaneously
    2. Cells have the same chemical components
    3. Organisms are composed of one or more cells
    4. Cells work together for an organism to function
48. Which of the following is at the lowest level of energy in an ecosystem?
    1. Producer
    2. Consumer
    3. Carnivore
    4. Decomposer
49. Energy flow in an ecosystem is:
    1. Unidirectional
    2. Bidirectional
    3. Cyclic
    4. Multidirectional
50. Which of the following is an example of mutualism?
    1. Bee and nectar
    2. Lion and zebra
    3. Orchid and tree
    4. Tick on cattle
51. Which of the following indicates parasitism?
    1. Tick on cattle
    2. Remora on shark
    3. Mycorrhiza on roots
    4. Nitrogen-fixing bacteria in legumes
52. A single mutation in a nucleotide leads to a change in the genetic constitution of an organism and can spread through a population by?
    1. Pleiotropy
    2. Epistasis
    3. Genetic Drift
    4. Polyploidy
53. Which cell organelle is responsible for cell rigidity and storage?
    1. Vacuole
    2. Ribosome
    3. Lysosome
    4. Mitochondrion
54. An ecosystem is represented as:
    1. Biotic components + Abiotic environment
    2. Population and community
    3. Population + Habitat
    4. Species + Niche
55. A lion and a hyena competing for the same food source is an example of:
    1. Interspecific competition
    2. Intraspecific competition
    3. Commensalism
    4. Mutualism
56. Which of the following scientists called for the classification of animals based on natural affinity?
    1. John Ray
    2. Carl Linnaeus
    3. Aristotle
    4. Charles Darwin
57. The core of cilia and flagella is known as the:
    1. Axoneme
    2. Nucleus
    3. Actin
    4. Centriole
58. What is the cellular shape of a neuron?
    1. Irregular with long extensions
    2. Cuboidal
    3. Spherical
    4. Columnar
59. The cytoskeleton is mainly composed of:
    1. Filamentous proteins
    2. Phospholipid bilayers
    3. Polysaccharides
    4. Cytoplasmic DNA
60. Who was the first to observe chromosomes during cell division in plant cells?
    1. Hofmeister
    2. Waldeyer
    3. Strasburger
    4. Robert Hooke
61. Lions and hawks, as top predators, are typically categorized as which level of consumers?
    1. Producers
    2. Primary consumers
    3. Secondary consumers
    4. Tertiary consumers
62. Which macromolecules are the primary components found within the nucleus?
    1. Nucleic acids and proteins
    2. Carbohydrates and lipids
    3. Phospholipids and steroids
    4. Polysaccharides and minerals
63. What type of symbiosis exists when a smaller organism eats insects and dead skin cells from a larger organism?
    1. Mutualism
    2. None of the above
    3. Commensalism
    4. Parasitism
64. Spindle fibers originate from which organelle during cell division in animal cells?
    1. Ribosome
    2. Centriole
    3. Lysosome
    4. Mitochondrion
65. In an adequate supply of water and oxygen, many types of algae reproduce primarily by:
    1. Budding
    2. Fragmentation
    3. Binary fission
    4. Spore formation
66. A plant that possesses only one type of reproductive part in a single flower is described as:
    1. Dioecious
    2. Unisexual
    3. Bisexual
    4. Monoecious
67. Which of the following leads to evolutionary adaptation?
    1. Predation
    2. Artificial selection
    3. Somatic mutation
    4. Acclimatization
68. Which of the following processes do animals perform, but plants do not?
    1. Photosynthesis
    2. Locomotion
    3. Respiration
    4. Reproduction
69. The cell organelle that is jelly-like where all other organelles are suspended is:
    1. Cytoplasm
    2. Nucleoplasm
    3. Cell wall
    4. Plasma membrane
70. The DNA part that appears when the chromosome is aligned is:
    1. Spindle fibers
    2. Centrioles
    3. Chromatin
    4. Centromere
71. The enzymes for ATP synthesis in the mitochondria are located in the:
    1. Matrix
    2. Outer membrane
    3. Stroma
    4. Lamella
72. Which of the following is not a chromosomal protein?
    1. Histone
    2. SHC
    3. Topoisomerase
    4. Cohesin
73. A good classification system does not have to?
    1. Contain all animals
    2. Be accepted by all zoologists
    3. Contain scientific names
    4. Enable easy retrieval of information
74. The relationship between bacteria and a dead dog is?
    1. Metabiosis
    2. Commensalism
    3. Inquilinism
    4. Phoresy
75. Which of the following is not a feature of heterochromatin as opposed to euchromatin?
    1. DNA is inactive
    2. It replicates earlier
    3. It is darkly stained
    4. Highly coiled
76. Which organism normally brings energy into the ecosystem?
    1. Primary consumer
    2. Decomposer
    3. Producer
    4. Secondary consumer
77. Mycoplasma is smaller than bacteria:
    1. True
    2. False
    3. Partly true
    4. Cannot be determined
78. The frog feeds on insects; what is the role of the frog?
    1. Producer
    2. Primary consumer
    3. Secondary consumer
    4. Decomposer
79. A virus is smaller than?
    1. Ribosome
    2. Most bacteria
    3. Protein
    4. Mitochondrion
80. Clownfish have protection from predators by living among which of the following organisms?
    1. Sea anemone
    2. Coral reefs
    3. Sponges
    4. Jellyfish
81. Genetic materials are encoded in:
    1. Carbohydrates
    2. Proteins
    3. Genes
    4. Lipids
82. Saprotrophs perform the following except?
    1. Extracellular digestion
    2. Secretion of enzymes
    3. Absorption
    4. None of the above
83. The organelle that detoxifies harmful substances is?
    1. Peroxisome
    2. Golgi apparatus
    3. Lysosome
    4. Ribosome
84. The shape of cells is determined by?
    1. Functions and cytoplasmic structure
    2. Availability of nutrients
    3. Environmental temperature
    4. Type of cell wall only
85. Which of the following is an example of interspecific competition?
    1. Two lions fighting over the same territory
    2. A lion and a cheetah both preying on zebras in the same habitat
    3. A pride of lions hunting together
    4. A lioness competing with her cubs for food
86. Which type of association involves physiological contact?
    1. Mutualism
    2. Commensalism
    3. Symbiosis
    4. Predation
87. Which of the following is not studied in taxonomy?
    1. Rules
    2. Practice
    3. Principles
    4. Properties
88. What is the biological relationship between a barnacle and a whale?
    1. Mutualism
    2. Commensalism
    3. Predation
    4. Parasitism
89. Kingdom Archaea consists of organisms such as:
    1. Methanogens
    2. Redwood trees
    3. Daisies
    4. Mushrooms
90. The female reproductive parts of plants are?
    1. Stigma, Style, and Ovary
    2. Anther, Filament, and Pollen
    3. Petal, Sepal, and Receptacle
    4. Xylem, Phloem, and Cambium
91. Which of the following is an example of an acellular organism?
    1. Virus
    2. Spirogyra
    3. Paramecium
    4. Amoeba
92. An example of commensalism is?
    1. Suckers on the body of sharks
    2. Ticks on a dog
    3. Fungi on a dead log
    4. Bacteria in the human gut
93. In the hierarchy of classification, what comes immediately after class?
    1. Order
    2. Kingdom
    3. Phylum
    4. Family
94. A ripened ovule develops into a?
    1. Seed
    2. Fruit
    3. Flower
    4. Spore
95. The process by which plant parts form a new plant is called?
    1. Vegetative propagation
    2. Sexual reproduction
    3. Pollination
    4. Fertilization
96. Which of the following is an example of a predator-prey relationship?
    1. Zebra and Lion
    2. Remora and Shark
    3. Tapeworm and Human
    4. Bee and Flower
97. Which of the following are the four whorls of a flower?
    1. Petals, Sepals, Androecium, Gynoecium
    2. Calyx, Corolla, Androecium, Gynoecium
    3. Stigma, Style, Anther, Filament
    4. Receptacle, Pedicel, Ovary, Ovule
98. The biological Domain is classified into:
    1. Monera, Eukarya, Archaea
    2. Archaea, Bacteria, Eukarya
    3. Plantae, Monera, Eukarya
    4. Animalia, Protista, Fungi
99. Who is the scientist famous for studying and naming approximately 12,000 species of plants and animals?
    1. Charles Darwin
    2. Carolus Linnaeus
    3. Gregor Mendel
    4. Robert Hooke
100. Which of the following best describes systematics?
     1. Classifying organisms to show evolutionary trends
     2. Constructing evolutionary relationships between organisms
     3. Naming organisms according to their habitat
     4. Studying the internal anatomy of organisms

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