Chapter 1: How do Plants Grow and Reproduce?
Find and record the definition of these words.
A seed plant that reproduces with cones
The movement of pollen from a stamen to a pistil or from a male cone to a female cone
when a sperm and an egg cell join.
when the seeds of a plant are carried to a new place.
all the stages a living thing goes through as it grows and reproduces.
Characteristics that are passed from parents to their offspring.
When a seed starts to grow
help attract insects and other animals, as well as protect the flower bud.
the female part of the flower
A young plant
the male part of the flower
A series of major changes in an animal’s body form during its life cycle
Groups of Plants p. 10-11
Scientists classify plants according to the way they reproduce.
To reproduce means to make more of its own kind.
Plants reproduce using seeds or spores.
Two types of seed plants: flowering and conifers.
Flowering plants- seeds grow in fruits
Conifers- seeds grow in cones
3 ways plants reproduce:
- With spores
- With seeds made in flowers- this method is most common
- With seeds made in cones
Flowers p. 12-15
Plants do not have flowers to look pretty. Plants have flowers to make seeds and fruits.
Parts of a flower:
Petals- color and shape of petals attract insects and animals. Petals protect flower bud as it grows.
Pistil- female part of the flower
Ovary- base of the pistil
Ovules- inside the ovary
Stamen- male part of the flower
Pollen- orange powder made by the stamen
Label the parts of the flower:
Pollination- the movement of pollen from a stamen to a pistil
Insects drink nectar that is deep inside flowers. The insect’s body brushes against the stamen and picks up the pollen. When the insect travels to the next flower, its body brushes against thepistilleaving pollen from the first flower. This causes pollination to occur.
Birds and bats can pollinate flowers too.
Wind pollinates many flowers and grasses.
Fertilization- the joining of an egg and sperm cell
Pollen lands on sticky surface of the pistil. A thin tube forms down through the pistil to the ovary. When tube reaches the ovule, the sperm cell joins the egg.
Fruits and Seeds p. 16-21
After fertilization, seeds and fruits begin to grow.
Seeds develop inside the ovaries.
Each seed holds everything the plant needs to grow.
3 main parts of a seed:
- Embryo- will grow into the new plant
- Seed coat- protects embryo and keeps it from drying out
- Stored food- helps the embryo to grow, also known as the seed leaf
Fruits- grow from the walls of ovaries that surround the seeds
Fruits protect and help spread the seeds
Different fruits have different numbers of seeds. Examples: cherries have one seed, apples have many seeds, walnuts have hard exterior and the nut we eat is the seed.
Seed dispersal- seeds cannot move from place to place by themselves, something must carry them
Poop system- animals eat the fruit or seeds, go to another location, then poop, seed is left behind in a new location. Seed is sitting in perfect fertilizer to take root and grow in the new place!
Hooks- some seeds have hooks that stick in an animal’s fur. When the animal moves to a new location, the seeds drop off and take root there.
Wind- some seeds are carried by the wind. Some seeds seem to have wings which help them to spin through the air. Dandelions also spread through the wind.
Water- some seeds are spread by water. Coconuts and palm trees have seeds that are carried on the ocean waves to new locations.
Germination and Growth
Seeds will not grow unless they have enough water.
Germination of a seed:
- Seed takes in water
- Seed coat breaks open
- Roots grow downward
- Stem and leaves grow upward
Seedling- ayoung plant
Seedling uses food that was stored in the seed to grow. When new leaves grow, plant begins to make its own food using photosynthesis.
Photosynthesis- the process by which plants turn water and carbondioxide into food when the plant is exposed to light
A seedling continues to grow, the stem gets longer, the roots grow deeper and wider. Over time, the seedling turns into a mature plant that is able to reproduce.
We Need Honeybees pages 22-23
Honeybees pollinate flowers by moving from flower to flower. Their bodies carry pollen from one flower to the next.
Honeybees pollinate many crops such as almonds, apples and strawberries.
Many bees are dying due to mites. Mites are tiny animals that live on bees and make it hard for the bee to fly.
Beekeepers are trying to protect the bees from the mites because our food crops depend on bees for pollination.
Life Cycles of Seed Plants pages 24-29
All flowering plants go through a similar life cycle.
Life Cycle- all the stages a living thing goes through as it grows and reproduces.
Four stages in the life cycle:
- Germination- when the seed begins to grow
- Growth- seedling grows into plant
- Maturity- plant is full grown and ready for pollination
- Seed formation- pollination occurs and seeds form in fruits, flowers or cones
Life cycles of conifers-
Pine trees have two kinds of cones, male and female.
Male cones- make pollen
Female cones- make seeds after they are pollinated by the wind
Female cone protects the seed as it grows and open when the conditions are right for the seed to grow.
Comparing Seed Plants:Reproductive Structures / Pollination / Location of Seeds
Plants / ______/ Most pollinated by ______
Some pollinated by ______/ In ______
Conifers / ______/ All are pollinated by ______/ In ______
Characteristics of Plants pages 30-34
Inherited characteristics – characteristics passed from parents to their offspring
Examples: shape of leaves and flowers, color of petals, taste of fruit, overall shape of plant
How the environment affects plants
Environment can change the way a plant grows.
A plant may receive little water and it will be smaller than a plant of the same type that grew in an environment with plenty of water.
Environmental conditions that affect plants:
- Amount of sunlight- too much sunlight or not enough sunlight can cause the plant to grow less quickly
- Amount of water- too much water or not enough water can cause the plant to grow less quickly
- Available space for growth- a small container can stunt a plant’s growth
- Wind- wind can determine the location of leaves and branches
- Human actions- we can contain plants in yards, pots, etc…