FLOWERS AND SEEDS The Structure of a Flower The flower is the seed factory of the plant – where the flower produces seeds. Let’s check out the flower: There are many significant parts to a flower… A flower’s sepals cover a developing flower bud in order to protect the bud while it grows. The petals of a flower are often bright and colorful, which attract insects and animals to the flower and aid in pollination. The stamen is the male part of a flower. It includes the anther and the filament. The filament is a thin structure. Anthers are at the top of each filament. The anther contains pollen that is a necessary ingredient to plant reproduction. The pistil of a flower includes the stigma, style, and ovary. Eggs can be found at the bottom of the pistil. The stigma is at the tip of the style of the pistil. Pollen collects on the stigma of flowers. The ovary of a flower contains seeds. The ovule is the part of the plant that becomes a fruit. Lesson Checkpoint: Where does pollen collect on flowers? An Imperfect Flower? Can you believe that there is such a thing as an imperfect flower?? A perfect flower is a flower with both a stamen and a pistil. An imperfect flower is a flower with only a stamen OR a pistil, not both. © Copyright NewPath Learning. All Rights Reserved. Permission is granted for the purchaser to print copies for non-commercial educational purposes only. Visit us at www.NewPathLearning.com.
Flower Pollination & Fert ilization These processes are the keys to a flower’s reproduction process. Pollination is the first step in flower reproduction. Here is how it happens: 1. Pollen sticks to an insect or animal from the anthers of one flower. 2. When that same insect or animal goes to another flower of the same kind, the insect or animal deposits the pollen onto the stigma of that flower. 3. Pollen tubes grow from the pistil of the flower down to the egg cells. 4. The sperm cells from the pollen go from the stigma down the style through the pollen tubes to the ovary of the flower. 5. When an ovule is fertilized, the DNA information from the pollen combines with the DNA information of the ovule and a seed is created. Lesson Checkpoint: How does pollination occur? © Copyright NewPath Learning. All Rights Reserved. Permission is granted for the purchaser to print copies for non-commercial educational purposes only. Visit us at www.NewPathLearning.com.
Two types of pollination Cross-pollination is the transfer of pollen from the anther of one flower to the stigma of another flower. Self-pollination is the transfer of pollen from anther to stigma on the same flower or to the stigma of another flower on the same plant. The Structure of a Seed Seeds have three main parts: a seed coat, embryo, and endosperm. The seed coat (the outer layer of the seed – like a coat you wear when it’s cold outside) protects the seed until it is ready to germinate. The embryo is the new plant waiting to grow inside the seed, and the endosperm is stored food inside the seed. How do seeds get around? Seeds are dispersed in several different ways. Seeds sometimes just fall from the parent flower onto the soil nearby the parent plant. Other seeds are dispersed by animals moving them from one place to another. Still others are eaten by animals and then go through the animal’s digestive system. When the animal rids its body of waste, the seeds are then dispersed in soil where the seeds can germinate when the conditions are right – talk about instant fertilizer! Lesson Checkpoint: What are two ways plant seeds are dispersed? © Copyright NewPath Learning. All Rights Reserved. Permission is granted for the purchaser to print copies for non-commercial educational purposes only. Visit us at www.NewPathLearning.com.
Germination When the conditions are right, a seed will germinate. Roots will grow out from the seed and down into the soil. The stem of the plant will then grow upwards. Ta da… a new plant is growing!! © Copyright NewPath Learning. All Rights Reserved. Permission is granted for the purchaser to print copies for non-commercial educational purposes only. Visit us at www.NewPathLearning.com.