Lesson 1 Energy Processing in Plants Chapter Introduction Lesson 1 Energy Processing in Plants Lesson 2 Plant Responses Lesson 3 Plant Reproduction Chapter Wrap-Up Chapter Menu

What processes enable plants to survive and reproduce? Chapter Introduction

What do you think? Before you begin, decide if you agree or disagree with each of these statements. As you view this presentation, see if you change your mind about any of the statements. Chapter Introduction

Do you agree or disagree? 1. Plants do not carry on cellular respiration. 2. Plants are the only organisms that carry on photosynthesis. 3. Plants do not produce hormones. Chapter Introduction

Do you agree or disagree? 4. Plants can respond to their environments. 5. Seeds contain tiny plant embryos. 6. Flowers are needed for plant reproduction. Chapter Introduction

Lesson 1 Reading Guide - KC Energy Processing in Plants How do materials move inside plants? How do plants perform photosynthesis? What is cellular respiration? How are photosynthesis and cellular respiration alike, and how are they different? Lesson 1 Reading Guide - KC

Lesson 1 Reading Guide - Vocab Energy Processing in Plants photosynthesis cellular respiration Lesson 1 Reading Guide - Vocab

Materials for Plant Processes Xylem and phloem—the vascular tissue in most plants—transport materials throughout a plant. Water flows inside xylem to all parts of a plant. Most plants make their own food; a liquid sugar that moves out of food-making cells, enters phloem, and flows to all plant cells. Lesson 1-1

Materials for Plant Processes (cont.) Carbon dioxide, oxygen, and water vapor pass into and out of a plant through tiny openings in leaves. How do materials move through plants? Lesson 1-1

Photosynthesis Photosynthesis is a series of chemical reactions that convert light energy, water, and carbon dioxide into the food-energy molecule glucose and give off oxygen. photosynthesis from Greek photo–, means “light”; and synthesis, means “composition” Lesson 1-2

Photosynthesis (cont.) Two types of mesophyll cells inside a leaf contain chloroplasts, the organelles where photosynthesis occurs. Near the top surface of the leaf are palisade mesophyll cells, which are packed together. Spongy mesophyll cells have open spaces between them, and gases needed for photosynthesis flow through the spaces. Lesson 1-2

Lesson 1-2

Photosynthesis (cont.) In the first step of photosynthesis, plants capture the energy in light. This occurs in chloroplasts, which contain plant pigments. Chlorophyll, the most common plant pigment, is necessary for photosynthesis. Lesson 1-2

Lesson 1-2

Photosynthesis (cont.) Sugars are made in the second step of photosynthesis. In chloroplasts, carbon dioxide and water are broken down and, using energy stored in chlorophyll, form sugar molecules. Lesson 1-2

Photosynthesis (cont.) What are the two steps of photosynthesis? Lesson 1-2

Cellular Respiration Cellular respiration is a series of chemical reactions that convert the energy in food molecules into a usable form of energy called ATP. Glucose molecules break down during cellular respiration. Plants produce sugar, but without cellular respiration, plants could not grow, reproduce, or repair tissues. Lesson 1-3

Cellular Respiration (cont.) What is cellular respiration? Lesson 1-3

Cellular Respiration (cont.) Most plants, some protists, and some bacteria carry on photosynthesis. Most organisms carry on cellular respiration. Life on Earth depends on a balance of these two processes. Lesson 1-3

Lesson 1-3

Lesson 1-4

Cellular Respiration (cont.) How are photosynthesis and cellular respiration alike, and how are they different? Lesson 1-4

Materials that a plant requires to survive move through the plant in the vascular tissue, xylem and phloem. Plants can make their own food by using light energy, water, and carbon dioxide. Lesson 1 - VS

The products of photosynthesis are the reactants for cellular respiration. Lesson 1 - VS

Which term refers to the organelles where photosynthesis occurs? A. palisade mesophyll cells B. chlorophyll C. chloroplasts D. spongy mesophyll cells Lesson 1 – LR1

Which process breaks down glucose molecules? A. cellular respiration B. light energy capture C. first step of photosynthesis D. second step of photosynthesis Lesson 1 – LR2

Which have open spaces between them that gases flow through? A. spongy mesophyll cells B. palisade mesophyll cells C. chloroplasts D. chlorophyll Lesson 1 – LR3

1. Plants do not carry on cellular respiration. Do you agree or disagree? 1. Plants do not carry on cellular respiration. 2. Plants are the only organisms that carry on photosynthesis. Lesson 1 - Now

Lesson 2 Reading Guide - KC Plant Responses How do plants respond to environmental stimuli? How do plants respond to chemical stimuli? Lesson 2 Reading Guide - KC

Lesson 2 Reading Guide - Vocab Plant Responses stimulus tropism photoperiodism plant hormone Lesson 2 Reading Guide - Vocab

Stimuli and Plant Responses Stimuli are any changes in an organism’s environment that cause a response. A plant responds to light by growing toward it. Lesson 2-1

Environmental Stimuli A tropism is a response that results in plant growth toward or away from a stimulus. When the growth is toward a stimulus, the tropism is called positive. Growth away from a stimulus is considered negative. Lesson 2-2

The growth of a plant toward or away from light is a tropism called phototropism Lesson 2-2

Environmental Stimuli (cont.) tropism from Greek tropos, means “turn” or “turning” Lesson 2-2

Environmental Stimuli (cont.) The response of a plant to touch is called a thigmotropism. Special structures that respond to touch, called tendrils, can wrap around or cling to objects. Lesson 2-2

Environmental Stimuli (cont.) The response of a plant to gravity is called gravitropism. Stems grow away from gravity, while roots grow toward gravity. Lesson 2-2

Environmental Stimuli (cont.) What types of environmental stimuli do plants respond to? Give three examples. Lesson 2-2

Environmental Stimuli (cont.) Photoperiodism is a plant’s response to the number of hours of darkness in its environment. Plants that flower when exposed to less than 10-12 hours of darkness are called long-day plants. Lesson 2-2

Environmental Stimuli (cont.) Short-day plants require 12 or more hours of darkness for flowering to begin. Day-neutral plants flower when they reach maturity and the environmental conditions are right. Lesson 2-2

The number of hours of darkness controls flowering in many plants. Lesson 2-2

Chemical Stimuli Plant hormones are substances that act as chemical messengers within plants. Auxins are hormones responsible for phototropism. They cause the cells on the dark side of the plant’s stem to grow longer. Lesson 2-3

Chemical Stimuli (cont.) The plant hormone ethylene helps stimulate the ripening of fruit. Ethylene is a gas that can be produced by fruits, seeds, flowers, and leaves. How do plants respond to the chemical stimuli, or hormones, auxin and ethylene? Lesson 2-3

Chemical Stimuli (cont.) Rapidly growing areas of a plant, such as roots and stems, produce gibberellins, which increase the rate of cell division and cell elongation. Root tips produce cytokinins, a hormone that increases the rate of cell division and, in some plants, slows the aging process of flowers and fruits. Lesson 2-3

Humans and Plant Responses Humans make plants more productive by using plant hormones. Some crops now are easier to grow because humans understand how plants respond to hormones. Lesson 2-4

Plants respond to stimuli in their environments in many ways. Lesson 2 - VS

Photoperiodism occurs in long-day plants and short-day plants Photoperiodism occurs in long-day plants and short-day plants. Day- neutral plants are not affected by the number of hours of darkness. Lesson 2 - VS

Plant hormones are internal chemical stimuli that produce different responses in plants. Lesson 2 - VS

Which term refers to the growth of a plant toward or away from light? A. phototropism B. photoperiodism C. gravitropism D. thigmotropism Lesson 2 – LR1

Which of the following helps stimulate the ripening of fruit? A. auxins B. cytokinins C. ethylene D. none of these Lesson 2 – LR2

Which refers to special plant structures that respond to touch? A. roots B. stems C. leaves D. tendrils Lesson 2 – LR3

3. Plants do not produce hormones. Do you agree or disagree? 3. Plants do not produce hormones. 4. Plants can respond to their environments. Lesson 2 - Now

Lesson 3 Reading Guide - KC Plant Reproduction What is the alternation of generations in plants? How do seedless plants reproduce? How do seed plants reproduce? Lesson 3 Reading Guide - KC

Lesson 3 Reading Guide - Vocab Plant Reproduction embryo seed stamen pistil ovary fruit alternation of generations spore pollen grain pollination ovule Lesson 3 Reading Guide - Vocab

Asexual Reproduction Versus Sexual Reproduction Asexual reproduction occurs when a portion of a plant develops into a separate new plant that is genetically identical to the original, or parent, plant. Sexual reproduction occurs when a plant’s sperm combines with a plant’s egg. The resulting zygote can grow into a plant that is a genetic combination of its parents. Lesson 3-1

Humans live their entire lives as diploid organisms Humans live their entire lives as diploid organisms. Some organisms have haploid and diploid stages called generations. Lesson 3-2

Alternation of Generations Alternation of generations is when the life cycle of an organism alternates between diploid and haploid generations. generation Science Use haploid and diploid stages in the life cycle of a plant Common Use the average span of time between the birth of parents and their offspring Lesson 3-2

Alternation of Generations (cont.) What is alternation of generations in plants? Lesson 3-2

Alternation of Generations (cont.) Meiosis occurs in certain cells in the reproductive structures of a diploid plant. The daughter cells produced from haploid structures are called spores. spore from Greek spora, means “seed, a sowing” Lesson 3-2

Alternation of Generations (cont.) Spores grow by mitosis and cell division and form the haploid generation of a plant. Certain reproductive cells of the haploid generation produce haploid sperm or eggs by mitosis and cell division. Fertilization takes place when a sperm and an egg fuse and form a diploid zygote. Lesson 3-2

Reproduction in Seedless Plants Seedless plants grow from haploid spores, not from seeds. Mosses grow by mitosis and cell division from haploid spores produced by the diploid generation. Lesson 3-3

Reproduction in Seedless Plants Ferns produce haploid spores that grow into tiny plants which produce eggs and sperm that can unite and form the diploid generation. Lesson 3-3

Reproduction in Seedless Plants (cont.) How do seedless plants such as mosses and ferns reproduce? Lesson 3-3

How do seed plants reproduce? Unlike seedless plants, the haploid generation of a seed plant is within diploid tissue. Separate diploid male and diploid female reproductive structures produce haploid sperm and haploid eggs that join during fertilization. Lesson 3-4

How do seed plants reproduce? (cont.) A pollen grain forms in a male reproductive structure of a seed plant. Pollen grains produce sperm cells which can be carried to female reproductive structures by wind, animals, gravity, or water currents. The female reproductive structure of a seed plant where the haploid egg develops is called the ovule. Lesson 3-4

Pollination occurs when pollen grains land on a female reproductive structure of a plant that is the same species as the pollen grains. Lesson 3-4

How do seed plants reproduce? (cont.) Following pollination, sperm enter the ovule and fertilization occurs. A zygote forms and develops into an embryo, an immature diploid plant. Lesson 3-4

How do seed plants reproduce? (cont.) An embryo, its food supply, and a protective covering make up a seed. Lesson 3-4

How do seed plants reproduce? (cont.) Lesson 3-4

How do seed plants reproduce? (cont.) Flowerless seed plants are known as gymnosperms. The most common gymnosperms are conifers, such as pines, firs, cypresses, redwoods, and yews. Cones are the male and female reproductive structures of conifers. Lesson 3-4

Reproduction in Flowerless Seed Plants Lesson 3-4

How do seed plants reproduce? (cont.) Flowering seed plants are called angiosperms. Reproduction of an angiosperm begins in a flower, most of which have male and female reproductive structures. Lesson 3-4

How do seed plants reproduce? (cont.) The male reproductive organ of a flower is the stamen. Pollen grains form at the tip of the stamen in the anther. Lesson 3-4

How do seed plants reproduce? (cont.) The female reproductive organ of a flower is the pistil. Pollen can land at the tip of the pistil, or stigma. The ovary is at the base of the style. It contains one or more ovules. Lesson 3-4

How do seed plants reproduce? (cont.) The ovary, and sometimes other parts of the flower, will develop into a fruit that contains one or more seeds. The seeds can grow into new, genetically related plants that produce flowers, and the cycle repeats. Lesson 3-4

Lesson 3-4

How do seed plants reproduce? (cont.) In most cases, seeds of flowering plants are inside fruits. Fruits help protect seeds and help scatter or disperse them. Lesson 3-4

The life cycle of a plant includes an alternation of generations. Lesson 3 - VS

Seedless plants, such as ferns and mosses, grow from haploid spores. In seed plants, pollination occurs when pollen grains land on the female reproductive structure of a plant of the same species. Lesson 3 - VS

In order for this to occur, pollen grains must land on a female reproductive structure of a plant. A. cell division B. meiosis C. pollination D. sexual reproduction Lesson 3 – LR1

Which term refers to the female reproductive organ of a flower? A. embryo B. pistil C. seed D. stamen Lesson 3 – LR2

C. asexual reproduction D. alternation of generations What term refers to the life cycle of an organism alternating between diploid and haploid generations? A. pollination B. meiosis C. asexual reproduction D. alternation of generations Lesson 3 – LR3

5. Seeds contain tiny plant embryos. Do you agree or disagree? 5. Seeds contain tiny plant embryos. 6. Flowers are needed for plant reproduction. Lesson 3 - Now

Interactive Concept Map Chapter Review Standardized Test Practice Key Concept Summary Interactive Concept Map Chapter Review Standardized Test Practice Chapter Review Menu

Plants transform light energy into chemical energy, respond to stimuli and maintain homeostasis, and reproduce with and without seeds. The BIG Idea

Lesson 1: Energy Processing in Plants The vascular tissues in most plants, xylem and phloem, move materials throughout plants. In photosynthesis, plants convert light energy, water, and carbon dioxide into the food-energy molecule glucose through a series of chemical reactions. The process gives off oxygen. Cellular respiration is a series of chemical reactions that convert the energy in food molecules into a usable form of energy called ATP. Photosynthesis and cellular respiration can be considered opposite processes of each other. Key Concepts 1

Lesson 2: Plant Responses Although plants cannot move from one place to another, they do respond to stimuli, or changes in their environments. Plants respond to stimuli in different ways. Tropisms are growth responses toward or away from stimuli such as light, touch, and gravity. Photoperiodism is a plant’s response to the number of hours of darkness in its environment. Plants respond to chemical stimuli, or plant hormones, such as auxins, ethylene, gibberellins, and cytokinins. Different hormones have different effects on plants. Key Concepts 2

Lesson 3: Plant Reproduction Alternation of generations is when the life cycle of an organism alternates between diploid and haploid generations. Seedless plants, such as ferns, reproduce when a haploid sperm fertilizes a haploid egg, forming a diploid zygote. Seed plants reproduce when pollen grains, which contain haploid sperm, land on the tip of the female reproductive organ. At the base of this organ is the ovary, which usually contains one or more ovules. Each ovule eventually will contain a haploid egg. If the sperm fertilizes the egg, an embryo will form within a seed. Key Concepts 2

Carbon dioxide, oxygen, and water vapor pass into and out of a plant through which part of a plant? A. leaves B. phloem C. roots D. xylem Chapter Review – MC1

Water flows to all parts of a plant in which of these? A. xylem B. phloem C. chloroplasts D. chlorophyll Chapter Review – MC2

Which term refers to a response that results in plant growth toward or away from a stimulus? A. photoperiodism B. photosynthesis C. stimuli D. tropism Chapter Review – MC3

When the growth is toward a stimulus, what is the tropism referred to as? A. negative B. photoperiodism C. photosynthesis D. positive Chapter Review – MC4

Which term refers to a male reproductive organ of a flower? A. ovary B. pistil C. stamen D. zygote Chapter Review – MC5

A. cellular respiration B. photosynthesis C. xylem D. phloem Which term refers to a series of chemical reactions that convert light energy, water, and carbon dioxide into the food-energy molecule glucose? A. cellular respiration B. photosynthesis C. xylem D. phloem Chapter Review – STP1

Where does the first step of photosynthesis occur? A. xylem B. phloem C. mesophyll cells D. chloroplasts Chapter Review – STP2

Which term describes any changes in an organism’s environment that cause a response? A. tropism B. gravitropism C. phototropism D. stimuli Chapter Review – STP3

Short-day plants require how many hours of darkness for flowering to begin? A. 12 or more B. 10 to 12 C. 8 to 10 D. less than 8 Chapter Review – STP4

Which term refers to the daughter cells produced from haploid structures? A. pollen grains B. seeds C. spores D. zygotes Chapter Review – STP5