Chapter 10 Section 5Get book and Open to

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Anticipatory Set

Reproduction in Seed Plants

Big Idea

California StandardsScience Standard 7.2.a:

Students know the differences between the life cycle and reproduction methods of sexual and asexual organisms.

Science Standard 7.5.f:Students know the structures and processes by which flowering

plants generate pollen, ovules, seeds, and fruit.

Characteristics of gymnosperms and

angiosperms.

InputGymnosperm – a seed plant that produces

naked seeds.Cones – gymnosperms reproductive

structures.

Ovule – a structure that contains an ovum, or egg cell.

Angiosperm – a flowering plant.

Flower – the reproductive structure of an angiosperm.

Input

Petals – The most colorful parts of the flower.

Pollination – the transfer of pollen from a male reproductive structure to a female reproductive structure.

Input

Ovary – protects the seeds as they develop.

Fruit – a ripened ovary and other structures that enclose one or more seeds.

Monocots – angiosperms that have only one seed leaf.

Dicots – angiosperms that have two seed leaves.

Input GymnospermsAll gymnosperms produce naked seeds. Many

gymnosperms have needle-like or scalelike leaves, and deep growing root systems.

Gymnosperms produce seeds that are not enclosed by fruits.

Gymnosperms are the oldest type of seed plants. (first appeared on earth about 360 million years ago.

Only four groups of gymnosperms exist today. (cycads, conifers, ginkgoes, and gnetophytes)

Input Types of Gymnosperms

Cycads175 million years ago, the majority of plants

were cycadsGrow mainly in the tropical and subtropical areasLook like palm trees with cones, and cones can

grow as large a a football

ConifersThe largest and most diverse group of

gymnosperms today.They are cone bearingKeep their leaves/needles all year longPines, sequoias, and junipers

Input Types of Gymnosperms

GinkgoesOnly one species exist today (ginko

biloba) Planted along city streets because they

can tolerate air pollutionGnetophytes

Live in hot deserts and tropical rainforests.

Consists of trees, shrubs and vines

Input Gymnosperm Life Cycle

Most gymnosperms have reproductive structures called cones.

Most gymnosperms produce two types of cones. Male cones and female cones.

Male cones produce tiny grains of pollen- the male gametophyte. The pollen contains the cells that later become sperm cells

Each scale on a male cone produces thousands of pollen grains.

Input Gymnosperm Life Cycle

The female gametophyte develops in structures called ovules.

Female cones contain at least one ovule at the base of each scale. After fertilization occurs the ovule develops into a seed.

Pollen falls from a male cone onto a female cone. A sperm cell and egg cell join together in an ovule on the female cone.

Input Differentation

Input How Cells Differentiate

During development, cells become fixed – or set- in how they will differentiate.

The instructions that will determine what will happen is coded in the DNA in its nucleus.

Differentiation occurs when certain sections of DNA are turned off. The active DNA then guides the development of the cell.

Once a cell’s future has been determined, when and how much it will changes depends on its DNA, its function, and the type of organism.

Some cells differentiate completely during development, others do not change until later.

Input Cell Differentiaton Among Animals

Once human cells differentiate, they usually lose their ability to become other types of cells.

Ex: a blood cell CANNOT change into a skin cellHumans do produce cells called STEM CELLS that

can differentiate throughout life. Stem Cells exist all around the body, and respond

to specific needs in the body by becoming specialized.

EX: production of red and white blood cells.

Input Angiosperms All angiosperms share two important traits.

1 They produce flowers2 In contrast with gymnosperms, which produce

uncovered seeds, angiosperms produce seeds that are enclosed in fruits.

Angiosperms live almost everywhere on earth. They grow in frozen areas in the Arctic, tropical jungles, barren deserts, and at the oceans edge.

unlike gymnosperms, angiosperms produce fruit.

Input Angiosperm Life Cycle

Finish the Front of Notes on your ownAcross Discipline: Language Arts (compare

and contrast the life cycles of a gymnosperm and angiosperm)

Patterns: Draw and label The Structure of a flower (page 393)

Question: Write a question and answer it.Different Perspectives: The differences in cell

differentiation from an animal cell and plant cellSummary: Write a summary of what you have

learned.

Finish the Front of Notes on your ownAcross Discipline: Language Arts (compare

and contrast the life cycles of a gymnosperm and angiosperm)

Patterns: Draw and label The Structure of a flower (page 393)

Question: Write two questions and answer them.Different Perspectives: The differences in cell

differentiation from an animal cell and plant cellSummary: Write a summary of what you have

learned.