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Biology · 100 Level
This is the complete lecture note for BIO 102 General Biology II, prepared for Biology students at 100 Level. You can read it online below, open it in the full viewer, or download the PDF for offline study. It pairs with the course's video lectures, so you can read and watch together.
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Course code: BIO 102 Course title: General Biology II Course credit load: 2 Units Series 1: Characteristics of Plant and Animal Kingdoms • Part 1.1: The Plant Kingdom o Sub Part 1.1.1: General characteristics of plants o Sub Part 1.1.2: Major divisions of the plant kingdom o Sub Part 1.1.3: External features of representative plants • Part 1.2: The Animal Kingdom o Sub Part 1.2.1: General characteristics of animals o Sub Part 1.2.2: Major phyla of the animal kingdom o Sub Part 1.2.3: External features of representative animals • Part 1.3: Similarities and Differences Between Plants and Animals o Sub Part 1.3.1: Shared characteristics of living organisms o Sub Part 1.3.2: Key differences between plants and animals o Sub Part 1.3.3: Comparison of cell structure • Part 1.4: Classification and Taxonomy o Sub Part 1.4.1: Principles of biological classification o Sub Part 1.4.2: The binomial nomenclature system o Sub Part 1.4.3: Importance of classification in biology
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Introduction Biology is the scientific study of living organisms. The two largest kingdoms of multicellular organisms are the Plant Kingdom (Plantae) and the Animal Kingdom (Animalia). Understanding their defining characteristics, internal organisation, and shared properties provides the foundation for all further study in ecology, physiology, and evolutionary biology. This Series surveys the unique features of plants and animals, the major groups within each kingdom, the similarities they share as living organisms, key structural differences, and the principles of biological classification and taxonomy. This knowledge is essential for interpreting everything that follows in General Biology II. Series Learning Outcomes Upon completing this Series, you should be able to: • SLO 1.1 state the general characteristics of the Plant Kingdom and describe the major divisions (Linked to Part 1.1), • SLO 1.2 describe the external features of representative plants from different divisions (Linked to Part 1.1), • SLO 1.3 state the general characteristics of the Animal Kingdom and describe the major phyla (Linked to Part 1.2), • SLO 1.4 describe the external features of representative animals from different phyla (Linked to Part 1.2), • SLO 1.5 list the characteristics shared by all living organisms and state the key differences between plants and animals (Linked to Part 1.3), • SLO 1.6 compare plant and animal cell structure (Linked to Part 1.3), and • SLO 1.7 explain the principles of biological classification and the binomial nomenclature system (Linked to Part 1.4).
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS 1.1 The Plant Kingdom 1.1.1 General characteristics of plants Plants are multicellular, eukaryotic organisms with cell walls made of cellulose. They are autotrophs, producing their own food through photosynthesis using chlorophyll pigments in specialised organelles called chloroplasts. Most plants are sessile (fixed in place) and show indeterminate growth throughout their life. They reproduce both sexually and asexually and are adapted to terrestrial and aquatic environments. Key plant characteristics: presence of cellulose cell walls; chloroplasts containing chlorophyll a and b; food stored as starch; large central vacuole in mature cells; absence of centrioles in most higher plants; and reproduction involving alternation of generations (a haploid gametophyte and diploid sporophyte phase). Most plants obtain water and mineral salts from the soil through roots and transport these upward through specialised vascular tissue. Fill in the blank: Plants are ________ organisms that produce their own food through photosynthesis using chlorophyll pigments in chloroplasts; their cell walls are composed of cellulose. 1.1.2 Major divisions of the plant kingdom The Plant Kingdom is divided into four major groups. Bryophytes (mosses, liverworts, hornworts): non-vascular; no true roots, stems, or leaves; depend on water for sexual reproduction; found in moist habitats. Pteridophytes (ferns, horsetails): vascular; true roots, stems, and leaves; reproduce by spores; no seeds. Gymnosperms (conifers, cycads, ginkgo): vascular; seeds borne naked on cones (not enclosed in fruit); produce pollen. Angiosperms (flowering plants): the largest and most diverse plant group; vascular; seeds enclosed in fruit; reproduce by flowers; divided into monocots (one seed leaf, parallel veins, fibrous root system) and dicots (two seed leaves, net veins, tap root system). Angiosperms dominate most terrestrial ecosystems and include virtually all crop plants of agricultural importance such as maize, cassava, yam, rice, tomato, and citrus.
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Fill in the blank: Angiosperms are divided into ________ (one seed leaf, parallel veins) and dicots (two seed leaves, net veins); they are the most diverse and dominant plant group on Earth. 1.1.3 External features of representative plants A typical dicot plant (e.g. Hibiscus or tomato) has: root (primary tap root with lateral roots; anchors the plant; absorbs water and minerals); stem (erect or climbing; supports leaves and flowers; transports water upward and food downward); leaves (flat blade called the lamina; petiole attaches to stem; veins carry vascular tissue; site of photosynthesis and gas exchange through stomata); and reproductive organs (flowers contain sepals, petals, stamens, and carpel). A typical monocot (e.g. maize) has: fibrous roots; hollow jointed stem called a culm; long narrow leaves with parallel veins and no petiole; and flowers grouped into inflorescences. Bryophytes such as mosses have rhizoids (root-like anchors), a flattened thallus or upright leafy shoot, and a sporophyte (spore-bearing structure) attached to the gametophyte. Ferns have fronds (leaves), rhizomes (horizontal underground stems), and sori (clusters of sporangia on the underside of fronds). Fill in the blank: The flat blade of a leaf is called the ________; it is connected to the stem by the petiole and contains veins that carry vascular tissue to and from the leaf.
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Figure 1.1: Labelled diagram of a typical dicot plant showing external features Pilot questions 1.1 1. State five general characteristics of the Plant Kingdom. 2. Distinguish between bryophytes and pteridophytes. 3. Distinguish between monocots and dicots with two examples each. 4. Name and describe the external features of a typical dicot plant. 5. Explain why angiosperms are more successful than gymnosperms.
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS 1.2 The Animal Kingdom 1.2.1 General characteristics of animals Animals are multicellular, eukaryotic organisms that lack cell walls and chloroplasts. They are heterotrophs, obtaining energy by ingesting and digesting organic matter. Most animals can move and respond rapidly to stimuli through a nervous system. Animal cells contain centrioles, which are absent from most plant cells. Food is stored as glycogen rather than starch. Growth in most animals is determinate (stops at maturity). Key animal characteristics: no cell walls (only a flexible plasma membrane); no chloroplasts; heterotrophic nutrition; food stored as glycogen; presence of nervous tissue; ability to move (in most animals); and reproduction that is predominantly sexual with internal or external fertilisation. Animals occupy virtually every habitat on Earth, from deep ocean trenches to high-altitude mountain peaks, and show extraordinary diversity in body plans, size, and lifestyle. Fill in the blank: Animals store food as ________ rather than starch; they lack cell walls and chloroplasts, and most obtain energy by ingesting and digesting organic matter from other organisms. 1.2.2 Major phyla of the animal kingdom Major invertebrate phyla: Porifera (sponges; no true tissues; filter feeders); Cnidaria (jellyfish, coral, hydra; radial symmetry; stinging cells called nematocysts); Platyhelminthes (flatworms, tapeworms; acoelomate; dorsoventrally flattened); Nematoda (roundworms; pseudocoelomate; cylindrical; many are parasites); Annelida (earthworms, leeches; true coelom; segmented body); Mollusca (snails, clams, squids; soft body; many have shells); Arthropoda (insects, spiders, crabs; jointed legs; exoskeleton; largest animal phylum). Phylum Echinodermata (sea stars, sea urchins): spiny skin; radial symmetry in adults; water vascular system. Phylum Chordata contains all vertebrates: Class Chondrichthyes (sharks; cartilaginous skeleton); Class Osteichthyes (bony fish); Class Amphibia (frogs, salamanders; moist skin; semi-aquatic); Class Reptilia (lizards, snakes; dry scaly skin; amniote egg); Class
BIO la-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Aves (birds; feathers; endothermic); Class Mammalia (hair; mammary glands; endothermic; most viviparous). Fill in the blank: Arthropoda is the largest animal phylum; its members have ________ legs, an exoskeleton, and a segmented body; it includes insects, spiders, centipedes, and crustaceans. 1.2.3 External features of representative animals An earthworm (Lumbricus terrestris) shows: segmented cylindrical body; mouth at anterior end; anus at posterior end; clitellum (swollen saddle-shaped segment for reproduction); setae (small bristles on each segment for movement). A grasshopper (Arthropoda, Insecta) shows: head (antennae, compound eyes, mouthparts); thorax (three pairs of jointed legs, two pairs of wings); abdomen (digestive and reproductive organs); tough exoskeleton of chitin. A frog (Amphibia) shows: moist smooth skin; two bulging eyes; tympanic membrane (ear drum) behind the eye; nostrils; webbed hind feet adapted for swimming; no tail in adults. A mammal such as a rabbit shows: body covered in fur; external pinnae (ears); vibrissae (whiskers); four limbs with claws; tail; and visible nostrils. External features reflect ecological adaptations to the animal's
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