2What Do Different Plant Parts Do? RootsRoots act like straws absorbing water and minerals from the soil. Tiny root hairs stick out of the root, helping in the absorption. Roots help to anchor the plant in the soil so it does not fall over. Roots also store extra food for future use.
3StemsStems do many things. They support the plant. They act like the plant's plumbing system, conducting water and nutrients from the roots and food in the form of glucose from the leaves to other plant parts. Stems can be herbaceous like the bendable stem of a daisy or woody like the trunk of an oak tree.
4LeavesMost plants' food is made in their leaves. Leaves are designed to capture sunlight which the plant uses to make food through a process called photosynthesis. The lower epidermis of a leaf has many small openings called stomata. Stomata usually open during the day so the leaf can take in carbon dioxide to make food. Stomata close at night to keep the plant from drying out. The loss of water through leaves is called transpiration.
5FlowerFlowers are the reproductive part of most plants. Flowers contain pollen and tiny eggs called ovules. After pollination of the flower and fertilization of the ovule, the ovule develops into a fruit.
6PhotosynthesisPlants use photosynthesis to make food. This process uses water from the soil, carbon dioxide from the air and energy from sunlight. Plant cells contain chloroplasts are found in the inner layers of leaves on most plants. Only cells with chloroplasts can make food.
8It all starts with plants ProducersAll organisms need energy to live and grow. That energy comes from food. Plants are called producers because they produce, or make, their own food.ConsumersWhen animals eat plants, the animals receive the energy that’s stored in those plants. The word consume means “to eat,” so we call animals that eat plants or other animals consumers
9Several parts of a plant help in photosynthesis The rootsTake in water and nutrientsThe stemKeeps the leaves in the sunlight; carries water to leavesThe leavesUse light energy, water, and carbon dioxide to make food
10Energy Transfer What is an ecosystem? All living and nonliving things interacting in an areaHerbivoreAn animal that eats plants or other producers. Herbivores are also called first-level consumers.CarnivoreAn animal that eats mainly other animals. Carnivores are also called second-level consumersOmnivoresAnimals that eat both plants and other animals. They can be first-level or second-level consumers.
11A food chain is the transfer of food energy between organisms A food chain is the transfer of food energy between organisms. Each time something eats something else, food energy is transferred from one organism to the next. For example, a simple food chain links the trees & shrubs, the giraffes (that eat trees & shrubs), and the lions (that eat the giraffes). Each link in this chain is food for the next link. A food chain always starts with plant life and ends with an animal.Decomposer is a consumer that gets its food energy by breaking down the remains of dead organisms. Decomposers can be animals, such as earthworms. Decomposers use some of the nutrients as food. The rest become mixed into the soil. Then plant roots can take up these nutrients. In this way, decomposers connect both ends of a food chain.The producers make food, then food energy is transferred through the ecosystem from one consumer level to another. All along the way, decomposers get energy from the remains of dead organisms. Any nutrients not used are returned to the soil.
12Food WebsA food web shows the relationships among different food chains.The above energy pyramid shows many trees & shrubs providing food and energy to giraffes. Note that as we go up, there are fewer giraffes than trees & shrubs and even fewer lions than giraffes ... as we go further along a food chain, there are fewer and fewer consumers. In other words, a large mass of living things at the base is required to support a few at the top ... many herbivores are needed to support a few carnivores
13producer herbivore carnivore Transfer of Energyproducer herbivore carnivore
14Energy PyramidAn energy pyramid shows that each level of a food chain passes on less food energy than the level before it. Most of the energy in each level is used at that level. Only a little energy is passed on to the next level.**About 10 percent of energy is passed from each level of an energy pyramid to the next.
15Natural CyclesMost ecosystems depend on the water cycle to provide plants with the water they need for photosynthesis.Nitrogen CyclePlants use nitrogen compounds to grow.Lightning produces nitrogen compounds that dissolve in rain.Bacteria break down animal wastes and dead organisms.Bacteria that live on some plant roots fix nitrogen gas.