Lesson Notes By Weeks and Term v3 - Primary 4
Changes in Plants and Animals
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Changes in Plants and Animals
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Subject: Basic Science
Class: Primary 4
Term: 2nd Term
Week: 6
Theme: Living And Non-Living Things
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Watch on YouTubeSee Facebook postobserve and describe changes in plants record the changes observed observe and describe changes in different animals mention the names of the young on es of different animals state the major reasons for the observed changes draw and label the life cycle of some common animals
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Development / Maturation: As organisms grow, their body parts develop and become fully functional. This is a process of specialization, leading to the ability to reproduce.
Reproduction: Changes occur to enable organisms to reproduce and ensure the continuity of their species. For example, plants produce flowers and fruits, and animals develop reproductive organs.
Environmental Factors: External conditions like availability of food, water, sunlight (for plants), shelter, and suitable temperature can influence the rate and extent of growth and development. Lack of these essentials can stunt growth or prevent development.
Aging: Changes also occur as organisms get older, leading to senescence and eventual death, completing the life cycle. 2.
5. Life Cycle of Common Animals (Focus on Insects) A life cycle describes the series of changes an organism goes through from birth to reproduction and death. Complete Metamorphosis (e.g., Butterfly, Mosquito, Beetle): This type of life cycle has four distinct stages, each looking very different from the others.
1. Egg: The life cycle begins with an egg, usually laid on a leaf or in water.
2. Larva: The egg hatches into a larva (e.g., caterpillar for butterfly, wriggler for mosquito). The larva's main job is to eat and grow. It sheds its skin multiple times (molting).
3. Pupa: The larva transforms into a pupa (e.g., chrysalis for butterfly, tumbler for mosquito). This is a resting stage where major transformations occur inside a protective casing. The organism reorganizes its body structure.
4. Adult: The adult emerges from the pupa. The adult's main job is to reproduce.
Diagram: [Egg] -> [Larva/Caterpillar] -> [Pupa/Chrysalis] -> [Adult Butterfly] Incomplete Metamorphosis (e.g., Grasshopper, Cockroach, Termite): This type of life cycle has three stages, and the young ones (nymphs) resemble smaller versions of the adults, although they may lack fully developed wings and reproductive organs.
1. Egg: The life cycle begins with an egg.
2. Nymph: The egg hatches into a nymph. Nymphs look like miniature adults but are wingless and sexually immature. They grow by molting several times, gradually increasing in size and developing wings.
3. Adult: After several molts, the nymph develops into a fully grown adult with wings (if applicable) and reproductive capabilities.
Diagram: [Egg] -> [Nymph (small, wingless grasshopper)] -> [Adult Grasshopper] This section provides the core content knowledge for the teacher to deliver the lesson effectively. 2.
1. Changes in Plants Plants, like all living things, undergo a series of changes throughout their lifespan, from seed to maturity and eventual death. These changes are part of their growth and development.
Germination: This is the initial stage where a dormant seed begins to sprout and grow into a seedling. For germination to occur, seeds typically require warmth, water, and oxygen. The radicle (embryonic root) emerges first, followed by the plumule (embryonic shoot).
Example: A dry maize seed, when planted in moist soil, absorbs water, swells, and then a tiny root emerges, followed by a shoot.
Vegetative Growth: After germination, the seedling develops roots, stems, and leaves. During this phase, the plant increases in size (height and width), produces more leaves, and strengthens its stem. This growth is primarily focused on producing food through photosynthesis.
Example: A maize seedling grows taller, producing more broad leaves, and its stem thickens. Reproductive Growth (Flowering and Fruiting): Mature plants develop flowers, which are the reproductive organs. After pollination and fertilization, flowers develop into fruits containing seeds. This stage ensures the continuation of the plant species.
Example: A mature maize plant develops tassels (male flowers) and silks (female flowers) which, after pollination, lead to the formation of maize cobs (fruits) containing kernels (seeds). An okra plant produces flowers that develop into okra pods.
Senescence and Death: Eventually, plants age, their growth slows down, leaves may yellow and drop, and the plant gradually dies. This completes its life cycle. 2.
2. Changes in Animals Animals also experience significant changes as they grow from birth (or hatching) to adulthood. These changes involve increases in size, changes in body structure, and development of new abilities.
Growth: This refers to an irreversible increase in the size, mass, and volume of an animal. It involves an increase in the number and size of cells.
Example: A tiny chick hatches from an egg and gradually grows larger, heavier, and develops more feathers until it becomes a mature chicken (hen or cock). A puppy grows into a large dog.
Development: This involves changes in form and function, maturation of organs, and acquisition of new skills.
Example: A human baby develops the ability to crawl, then walk, talk, and eventually goes through puberty, which brings about significant physical and hormonal changes. A tadpole develops legs and loses its tail to become a frog.
Changes in Appearance: Many animals show distinct changes in their appearance as they mature.
Example: A goat kid might have softer fur and smaller horns than an adult goat. A caterpillar looks entirely different from an adult butterfly. 2.
3. Names of Young Ones of Different Animals It is important for learners to know the common terms for animal young ones. | Adult Animal | Young One | | :----------- | :-------------- | | Chicken | Chick | | Goat | Kid | | Dog | Puppy | | Cat | Kitten | | Cow | Calf | | Pig | Piglet | | Sheep | Lamb | | Duck | Duckling | | Frog | Tadpole (larva) | | Butterfly | Caterpillar (larva) | | Human | Baby / Infant | 2.
4. Reasons for Observed Changes The changes observed in plants and animals are primarily due to: Growth: Organisms take in nutrients (food, water, sunlight for plants) which they use to build new cells and increase the size of existing ones. This leads to an increase in overall size and weight.
Development / Maturation: As organisms grow, their body parts develop and become fully functional. This is a process of specialization, leading to the ability to reproduce.
Reproduction: Changes occur to enable organisms to reproduce and ensure the continuity of their species. For example, plants produce flowers and fruits, and animals develop reproductive organs. * Environmental Factors: External conditions like availability of food, water, sunlight (for plants), shelter, and suitable temperature can influence the rate and extent of growth and development. Lack of these essentials can stunt growth or prevent 3.
1. Teacher Activities Introduction (10 minutes): Begin by asking learners to think about how they have changed since they were babies.
Introduce the topic: "Changes in Plants and Animals," explaining that all living things change over time. Show pictures of a seed, a seedling, and a mature plant (e.g., a maize plant, bean plant). Ask learners to identify differences. Show pictures of a chick, a young goat (kid), and their adult forms (hen, goat). Ask them to point out differences.
Exploring Changes in Plants (15 minutes): Present actual plant samples (if available, e.g., a sprouted bean seed, a young bean plant, a mature bean plant with pods) or clear charts/diagrams showing the stages of plant growth (germination, seedling, mature plant, flowering/fruiting). Guide learners to observe specific changes: increase in size/height, number of leaves, presence of flowers/fruits. Facilitate a class discussion on "What changes do you see in these plants as they grow?" Explain the terms: germination, seedling, mature plant, flowering, fruiting. Exploring Changes in Animals & Naming Young Ones (20 minutes): Display charts or pictures of various adult animals and their young ones (e.g., dog-puppy, cat-kitten, cow-calf, chicken-chick, goat-kid). Point to each pair and ask learners to describe differences (size, colour, features like horns/feathers). Ask questions like, "What do we call the baby of a cow?" Consolidate by reviewing the names of young ones of different animals. Discussing Reasons for Changes (10 minutes): Lead a discussion: "Why do plants and animals change?" Guide learners to identify reasons such as: growth (getting bigger), development (body parts changing, becoming mature), and preparing to have their own young ones (reproduction). Emphasize that food, water, and sunlight (for plants) are essential for these changes. Introducing Animal Life Cycles (25 minutes): Explain the concept of a life cycle as a continuous journey of an organism from birth to death. Focus on the life cycle of a butterfly (complete metamorphosis) and a grasshopper (incomplete metamorphosis) using large, clear diagrams or a video. For the butterfly, clearly explain: Egg -> Larva (Caterpillar) -> Pupa (Chrysalis) -> Adult. For the grasshopper, clearly explain: Egg -> Nymph -> Adult. Emphasize the distinct stages and how each stage prepares the animal for the next.
Recap and Conclusion (5 minutes): Summarize the key points: Plants and animals grow and develop, have different stages, and change for reasons like growth and reproduction. Assign independent practice. 3.
2. Student Activities Observation and Discussion: Learners actively observe actual plants/pictures, identifying and discussing changes.
Naming Game/Drill: Participate in naming the young ones of different animals.
Drawing and Labeling: In their notebooks, learners draw simple sketches of plant growth stages or animal life cycles (as guided).
Question and Answer: Answer questions posed by the teacher regarding plant and animal changes.
Group Work (Optional): In small groups, learners can discuss changes they have observed in plants in their school compound or animals at home.
Recording: Learners record observations and key terms in their notebooks. These questions are designed to check immediate understanding and reinforce learning during the lesson. The teacher should guide learners through these questions, providing support and immediate feedback.
Question 1: Describe one change you would observe in a mango tree from when it is a small seedling until it produces fruit.
Solution: As a mango seedling grows, it increases in height and develops more leaves. Eventually, it will produce flowers which then develop into mango fruits. (Any one of these changes is acceptable, e.g., "It grows taller and produces more leaves," or "It starts bearing fruits.")
Commentary: This question targets Performance Objective 1 and 2, focusing on observing and describing plant changes.
Question 2: What are the young ones of the following animals called? a)
Chicken b)
Goat c)
Dog Solution: a)
Chicken: Chick b)
Goat: Kid c)
Dog: Puppy
Commentary: This question directly addresses Performance Objective 4, requiring learners to name animal young ones.
Question 3: Explain why a puppy grows into a bigger dog.
Solution: A puppy grows into a bigger dog primarily because of growth and development. It eats food, which provides nutrients. These nutrients are used by its body to produce more cells and increase the size of existing cells, causing the puppy to get bigger and stronger.
Commentary: This question targets Performance Objective 5, prompting learners to state the reasons for observed changes in animals.
Question 4: List the four main stages in the life cycle of a butterfly in the correct order.
Solution: Egg Larva (Caterpillar) Pupa (Chrysalis) Adult Butterfly
Commentary: This question targets Performance Objective 6, focusing on the life cycle of a common animal (insect).
Agriculture and Food Production: Learners can understand that the growth stages of plants (e.g., cassava, rice, tomatoes) determine when they are ready for harvest. Similarly, the growth of animals (e.g., chickens, goats) relates to when they are mature enough for consumption or reproduction, impacting local food security and livelihoods in Nigerian communities.
Environmental Stewardship: By learning about life cycles, learners appreciate the interconnectedness of living things. For example, understanding the life cycle of a mosquito helps in understanding disease prevention (e.g., malaria control by clearing breeding sites). Understanding the role of insects like butterflies in pollination highlights the importance of protecting local ecosystems.
Community Health and Development: Knowledge of human growth and development (linking to changes in animals) can be integrated into health education, teaching about proper nutrition for children to grow healthy and strong, preventing stunted growth common in some communities. It also provides a foundation for understanding hygiene practices as linked to insect life cycles.