IJMB 2025 BIOLOGY PAPER I QUESTIONS

IJMB 2025 BIOLOGY PAPER I QUESTIONS

IJMB 2025 BIOLOGY PAPER I QUESTIONS BELOW

 

IJMB 2025 BIOLOGY PAPER I SOLUTIONS BELOW

NUMBER 2

IJMB BIOLOGY.

(2)
i. ferns
ii. amyloplast
iii. aestivation
iv. isogamy
v. ascospores
vi. bacilli
vii. rhizoids
viii. psilophyta
ix. prokaryotes
x. mycelium

 

*IJMB BIOLOGY*

*NUMBER THREE*

(3i)
Synecology: Synecology is the branch of ecology that deals with the study of groups of different species of organisms that live together in a community and interact with one another and their environment. It focuses on understanding how species coexist, compete, and cooperate within a habitat, and how environmental factors such as temperature, humidity, and light affect community structure and composition.

(3ii)
Halophytes: Halophytes are plants that are adapted to grow in soils or waters with high salt concentrations, such as in coastal marshes, salt flats, and mangrove swamps. These plants have special adaptations like salt glands for excreting excess salt, succulent leaves for water storage, and deep root systems to access freshwater. They play a significant role in stabilizing saline environments and preventing soil erosion.

(3iii)
Biological control: Biological control is the method of controlling pests, diseases, and weeds using other living organisms such as predators, parasites, or pathogens. This technique is an environmentally friendly alternative to chemical pesticides and aims to maintain pest populations at manageable levels. For example, introducing ladybirds to control aphid populations in agriculture is a form of biological control.

(3iv)
Pollution: Pollution is the introduction of harmful substances or energy into the environment in quantities that cause adverse effects on living organisms and natural systems. It can occur in various forms, including air pollution, water pollution, soil pollution, and noise pollution. Common pollutants include industrial waste, vehicle emissions, plastic, and toxic chemicals, which degrade the quality of air, water, and land.

 

*IJMB BIOLOGY*

*NUMBER FOUR*

 

(4b)
=TYPES OF LICHENS=
(i) Crustose lichens: These form thin, flat crusts that are tightly attached to surfaces like rocks, tree bark, or soil. They cannot be removed without damaging the surface.
(ii) Foliose lichens: These have a leaf-like structure and are loosely attached to the substrate. They have distinct upper and lower surfaces and can be easily separated from the surface.
(iii) Fruticose lichens: These are shrubby or hair-like lichens that grow upright or hang down. They are often branched and attached at a single point.

=RANGE FORMS OF LICHENS=
(i) Leprose form: Powdery lichens made of loose granules without a distinct structure. They lack a well-organized thallus and are often found in shaded or moist environments.
(ii) Squamulose form: Consist of small, scale-like lobes that may overlap. They are intermediate between crustose and foliose forms.
(iii) Filamentous form: These are thread-like and composed of fine, filamentous strands. They often occur in humid or aquatic habitats.
(iv) Gelatinous form: These lichens swell and become jelly-like when wet. They are common in areas with high moisture and often contain cyanobacteria as the photosynthetic partner.

*IJMB BIOLOGY 1*

*NUMBER FIVE*

(5a)
Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy from the sun into chemical energy in the form of glucose (a type of sugar). This process occurs mainly in the chloroplasts of plant cells, which contain the green pigment chlorophyll.

(5b)
Vascular tissues in plants are specialized tissues that transport water, minerals, and nutrients throughout the plant. They form the vascular system, which is made up of two main types of tissues:

(i) Xylem: Responsible for transporting water and dissolved minerals from the roots to other parts of the plant. It also provides structural support. Xylem vessels are typically dead and hollow, allowing for efficient water flow.
(ii) Phloem: Transports the products of photosynthesis (mainly sugars) from the leaves to other parts of the plant where they are needed or stored. Phloem cells are living and include sieve tubes and companion cells.

 

*IJMB BIOLOGY*

*NUMBER SIX*

(6a)
Angiosperms: Angiosperms, also known as flowering plants, are the largest and most diverse group of plants in the plant kingdom. They are characterized by the presence of true flowers and seeds enclosed within a fruit. Angiosperms have well-developed vascular tissues (xylem and phloem) for the transport of water, minerals, and nutrients. They exhibit double fertilization, a unique reproductive process where one sperm fertilizes the egg to form a zygote, while the other fuses with two polar nuclei to form the endosperm. Angiosperms are classified into two main groups: monocotyledons (monocots) and dicotyledons (dicots), based on the number of seed leaves (cotyledons) in the embryo.

(6b)
Alternation of Generation: Alternation of generation is a biological process in which plants alternate between two multicellular stages in their life cycle: the haploid gametophyte and the diploid sporophyte. The gametophyte produces gametes (sperm and egg cells) through mitosis, which fuse during fertilization to form a diploid zygote. This zygote develops into the sporophyte, which then produces haploid spores through meiosis. These spores grow into new gametophytes, completing the cycle. This alternation ensures genetic variation and is found in all plants, though the dominant stage varies among plant groups, for example, the gametophyte is dominant in bryophytes, while the sporophyte is dominant in ferns, gymnosperms, and angiosperms.