Presentation in biology on the topic "human use of fruits and seeds." Presentation on the topic "seeds, fruits"

slide 2

The seed is a highly specialized organ of sexual reproduction, settling and experiencing adverse living conditions in seed plants, usually developing after fertilization from the ovule. Composition of seeds: Seeds are characterized by a certain chemical composition. All substances of the seed can be divided into two groups: inorganic and organic. Inorganic substances of seeds are represented by water and minerals. Even the driest-looking seeds contain 7 to 12% water. This can be verified by heating the seeds in a test tube. In this case, drops of water will form on the walls of the test tube. Seed characteristics

slide 3

When seeds are burned, ash remains, which is a mixture of various mineral salts. The seeds of all plants contain organic substances - proteins, fats and carbohydrates. However, their percentage in the seeds of different plants is not the same. In the seeds of some plants, a large amount of starch accumulates (66% for wheat, 67% for rye); in others - fats (in flax up to 48%, in castor beans up to 70%); in the third - proteins (for peas - 22-34%, for soybeans - 34-45%). In any case, the seeds contain all organic matter in greater or lesser quantities. Seed characteristics

slide 4

A typical seed consists of an integument (skin), an embryo, and nutritive tissue. Seed coat: Usually formed from the integument of the ovule. On the surface of the seed coat, you can see a small hole - the former seed entrance, or micropyle, as well as a scar - the place of the former attachment of the seed stalk. The main function of the seed coat is to protect the embryo from drying out, mechanical damage, etc. In addition, it promotes seed dispersal. Seed structure

slide 5

Embryo: Arises from a fertilized egg. It has a diploid set of chromosomes. The embryo is the main part of the seed, consisting of a root, a stalk, a bud with leaves, and one or two cotyledons (the first germinal leaves). Seed storage tissues - endosperm, perisperm, the main tissue of the cotyledons. Endosperm: The endosperm develops from the fertilized central nucleus of the embryo sac (has a triploid set of chromosomes). Seed structure

slide 6

Perisperm. The perisperm is the nutritional tissue of many seeds; it is formed from diploid nucellus cells and has a diploid set of chromosomes. Thus, the nutrients in the seed can be deposited in the perisperm, endosperm, or cotyledons. According to the nutrient content, seeds can be classified: Seed structure

Slide 7

Depending on the location of reserve nutrients, four or five types of seeds are distinguished: seeds with endosperm (poppy, wheat); seeds with perisperm (cockle); seeds with endosperm and powerful perisperm (pepper); seeds with nutrients in the germ (peas, beans); seeds with endosperm and nutrients in cotyledons (flax). Classification of seeds (for Olympiads)

Slide 8

Seeds with endosperm. Three main parts are distinguished in a grain of wheat: the seed coat, fused with the pericarp; seed germ; nutrient tissue - endosperm. The endosperm makes up the main part of the seed, represented by triploid cells with a supply of nutrients in the form of starch grains. On the periphery, the endosperm is surrounded by cells of the aleurone layer with a storage protein in the form of aleurone grains. The embryo is adjacent to the endosperm. In the embryo, a root, a bud with leaves, a stalk and one cotyledon, which is transformed into a shield (the second cotyledon is reduced), are clearly distinguishable. Seed classification

Slide 9

Seeds without endosperm and without perisperm on the example of a bean seed. Outside, the seed is covered with a thick skin, on the concave side of which one can find a scar and a micropyle. Under the skin is an embryo, consisting of two large cotyledons, having a kidney-shaped form, and located between them the germinal root, stalk and bud with leaves. After fertilization during the development of the seed, nutrients from the endosperm are absorbed by the embryo and deposited in the form of starch and aleurone grains in the cotyledons, so the cotyledons grow strongly. Seed classification

Slide 10

So, depending on the location of reserve nutrients, five types of seeds are distinguished: seeds with endosperm (poppy, wheat); seeds with perisperm (cockle); seeds with endosperm and powerful perisperm (pepper); seeds with nutrients in the germ (peas, beans); seeds with endosperm and nutrients in cotyledons (flax). Classification of seeds (for Olympiads)

slide 11

Olympians. What is indicated in the figure by the numbers 1 - 8? Testa; germinal root; germinal stalk; germinal kidney; Two cotyledons; Endosperm; Perisperm; Pericarp fused with the seed coat.

slide 12

slide 13

For seed germination, certain conditions are necessary, the main of which are: 1 - the presence of water; 2 - oxygen access; 3 - a certain temperature; 4 - living embryo of the seed. Seeds must swell before germination. In this case, the seeds absorb a large amount of water. This is necessary for the activation of enzymes that convert the reserve substances of the seed into a form that is easily digestible and accessible to the embryo. The seeds of some plants need to be scarified. Scarification - mechanical damage to the waterproof covers of the seed. It can be carried out manually or with the help of special mechanisms. seed germination conditions

Slide 14

Germinating seeds respire intensively. Oxygen is necessary for the implementation of redox processes that stimulate the division and growth of embryonic cells. They take in oxygen and release carbon dioxide. Raw grain collected in a pile is very hot - as a result of breathing, a lot of energy is released, which leads to the death of seed germs. Therefore, dry seeds are poured into the storages, the storages are ventilated. seed germination conditions

slide 15

Temperature is of great importance for seed germination. Seeds of many plants are able to germinate in a fairly wide range of temperatures. However, for each species there are certain upper and lower limits. For most plants, the minimum temperature is 0-5С, and the maximum is 45-48С. The optimum temperature for seed germination of many plants is 25-35°C. Conditions for seed germination Cold-resistant plants include rye, peas, and wheat. To heat-loving - melon, cucumber, tomatoes.

slide 16

Seeds of many plants of temperate and cold climatic zones do not germinate without freezing. Therefore, in agricultural practice, stratification is used - keeping seeds in wet sand at low temperatures. This technique accelerates the germination of seeds of many plants. seed germination conditions

Slide 17

The fruit is the reproductive organ of angiosperms, providing seed reproduction. Fruit functions: formation, protection and distribution of seeds. Fruits are characteristic only for flowering plants. The fruit is formed from the flower, usually after fertilization. The main role in the formation of the fetus is played by the gynoecium. The lower part of the pistil - the ovary, containing the ovules, grows and turns into a fruit. The fruit consists of a pericarp and seeds, the number of which corresponds to the number of ovules. Fruit

Slide 18

Sometimes other parts of the flower (stamens, perianth, receptacle) also take part in the formation of the fetus. Fruit structure: stalk; 1 - exocarp; 2 - mesocarp; 3 - endocarp; 4 - seed. The pericarp, or pericarp, is the wall of the fetus that develops from the wall of the ovary. As a rule, the pericarp makes up the bulk of the fetus. Three layers are usually distinguished in it: exocarp, the outer layer of the pericarp; mesocarp, middle layer of the pericarp; endocarp, the inner layer of the pericarp. Fruit

Slide 19

In different fruits, the layers of the pericarp are expressed in different ways. For example, in a drupe (the fruit of a cherry, peach), the exocarp is thin, leathery, the mesocarp is thick, juicy and fleshy, and the endocarp is hard woody (bone). In the hazel nut, the layers of the pericarp are practically indistinguishable. Fruit

Slide 20

There is no generally accepted classification of fruits. Distinguish a simple fruit - a fruit formed from the ovary of a single pistil (peas, cherries, poppies); complex, or prefabricated, fruit - a fruit formed from several pistils of one flower (raspberry, blackberry, buttercup). Fruit classification

"Wild and cultivated plants" - V group 3 level. Find a couple. Lily of the valley. Underline the plants of the Ivanovo region. Rye. Decorative. Corn. Cotton. Spinning. COMPLETE (at least three). Wild plant. Olive. Dress up. Herbs (tomato, ...). Raspberry. Pear. Watch, compare. Compare. Cereals (wheat, …). Dahlia. Herbs (dandelion, ...).

"Man and Plants" - Can a person live without plants? Research objectives: Hypothesis. Conclusion: Purpose of the study: RESULTS OF THE STUDY 1. A person breathes oxygen, which is released by plants. 3. Plants are a source of nutrition. Plants are an integral part of human life. By studying literature, I learned what benefits plants bring to humans.

"Distribution of fruits and seeds" - Burdock. Series. Human. Distribution methods. Wind. Water. Spreading. Dissemination of seeds and fruits. Birch. Avens. Spread by ants. Dandelion. Wind spread. Willow. Animals. Peas. Scattering (self-propagation). in the digestive system. Maple. Procurement of stocks.

"Indoor plants lesson" - Complete the task in the textbook on page 18. Cacti. Violets. Books are helpers. Dieffenbachia. Flowers in the house. Sunlight Heat Water Soil. Plant care guidelines. What conditions are necessary for plant life? Work plan: Hypothesis - assumption: Check. Complete the task in the textbook on page 19.

"Variety of plants" - Development of initiative and creativity of younger students, self-regulation. Tustikova Bibinur Amanbaevna, primary school teacher. The purpose of the experiment: Questioning of 4th grade students on the following tasks: The foundations of diligence, respect for nature are laid. The final third stage of the study was carried out using a questionnaire.

"Plants lesson" - Work with the textbook. "The world around" pp. 91-92. They die. The lower floor - herbs, mushrooms, mosses. Work in a notebook page 14 No. 15. "Brainstorming" is a problematic situation. Strawberry Birch Nettle Moss Mushroom Gooseberry. Independent reading with notes. Card work. The statement of scientists that "Plants are living beings."

In total there are 34 presentations in the topic

1 slide

Topic: Seeds, fruits Tasks: To study the structure of seeds of monocotyledonous and dicotyledonous plants, the structure and classification of fruits. Pimenov A.V.

2 slide

The seed is a highly specialized organ of sexual reproduction, settling and experiencing adverse living conditions in seed plants, usually developing after fertilization from the ovule. Composition of seeds: Seeds are characterized by a certain chemical composition. All substances of the seed can be divided into two groups: inorganic and organic. Inorganic substances of seeds are represented by water and minerals. Even the driest-looking seeds contain 7 to 12% water. This can be verified by heating the seeds in a test tube. In this case, drops of water will form on the walls of the test tube. Seed characteristics

3 slide

When seeds are burned, ash remains, which is a mixture of various mineral salts. The seeds of all plants contain organic substances - proteins, fats and carbohydrates. However, their percentage in the seeds of different plants is not the same. In the seeds of some plants, a large amount of starch accumulates (66% for wheat, 67% for rye); in others - fats (in flax up to 48%, in castor beans up to 70%); in the third - proteins (for peas - 22-34%, for soybeans - 34-45%). In any case, the seeds contain all organic matter in greater or lesser quantities. Seed characteristics

4 slide

A typical seed consists of an integument (skin), an embryo, and nutritive tissue. Seed coat: Usually formed from the integument of the ovule. On the surface of the seed coat, you can see a small hole - the former seed entrance, or micropyle, as well as a scar - the place of the former attachment of the seed stalk. The main function of the seed coat is to protect the embryo from drying out, mechanical damage, etc. In addition, it promotes seed dispersal. Seed structure

5 slide

Embryo: Arises from a fertilized egg. It has a diploid set of chromosomes. The embryo is the main part of the seed, consisting of a root, a stalk, a bud with leaves, and one or two cotyledons (the first germinal leaves). Seed storage tissues - endosperm, perisperm, the main tissue of the cotyledons. Endosperm: The endosperm develops from the fertilized central nucleus of the embryo sac (has a triploid set of chromosomes). Seed structure

6 slide

Perisperm. The perisperm is the nutritional tissue of many seeds; it is formed from diploid nucellus cells and has a diploid set of chromosomes. Thus, the nutrients in the seed can be deposited in the perisperm, endosperm, or cotyledons. According to the nutrient content, seeds can be classified: Seed structure

7 slide

Depending on the location of reserve nutrients, four or five types of seeds are distinguished: seeds with endosperm (poppy, wheat); seeds with perisperm (cockle); seeds with endosperm and powerful perisperm (pepper); seeds with nutrients in the germ (peas, beans); seeds with endosperm and nutrients in cotyledons (flax). Classification of seeds (for Olympiads)

8 slide

Seeds with endosperm. Three main parts are distinguished in a grain of wheat: the seed coat, fused with the pericarp; seed germ; nutrient tissue - endosperm. The endosperm makes up the main part of the seed, represented by triploid cells with a supply of nutrients in the form of starch grains. On the periphery, the endosperm is surrounded by cells of the aleurone layer with a storage protein in the form of aleurone grains. The embryo is adjacent to the endosperm. In the embryo, a root, a bud with leaves, a stalk and one cotyledon, which is transformed into a shield (the second cotyledon is reduced), are clearly distinguishable. Seed classification

9 slide

Seeds without endosperm and without perisperm on the example of a bean seed. Outside, the seed is covered with a thick skin, on the concave side of which one can find a scar and a micropyle. Under the skin is an embryo, consisting of two large cotyledons, having a kidney-shaped form, and located between them the germinal root, stalk and bud with leaves. After fertilization during the development of the seed, nutrients from the endosperm are absorbed by the embryo and deposited in the form of starch and aleurone grains in the cotyledons, so the cotyledons grow strongly. Seed classification

10 slide

So, depending on the location of reserve nutrients, five types of seeds are distinguished: seeds with endosperm (poppy, wheat); seeds with perisperm (cockle); seeds with endosperm and powerful perisperm (pepper); seeds with nutrients in the germ (peas, beans); seeds with endosperm and nutrients in cotyledons (flax). Classification of seeds (for Olympiads)

11 slide

Olympians. What is indicated in the figure by the numbers 1 - 8? Testa; germinal root; germinal stalk; germinal kidney; Two cotyledons; Endosperm; Perisperm; Pericarp fused with the seed coat.

12 slide

13 slide

For seed germination, certain conditions are necessary, the main of which are: 1 - the presence of water; 2 - oxygen access; 3 - a certain temperature; 4 - living embryo of the seed. Seeds must swell before germination. In this case, the seeds absorb a large amount of water. This is necessary for the activation of enzymes that convert the reserve substances of the seed into a form that is easily digestible and accessible to the embryo. The seeds of some plants need to be scarified. Scarification - mechanical damage to the waterproof covers of the seed. It can be carried out manually or with the help of special mechanisms. seed germination conditions

14 slide

Germinating seeds respire intensively. Oxygen is necessary for the implementation of redox processes that stimulate the division and growth of embryonic cells. They take in oxygen and release carbon dioxide. Raw grain collected in a pile is very hot - as a result of breathing, a lot of energy is released, which leads to the death of seed germs. Therefore, dry seeds are poured into the storages, the storages are ventilated. seed germination conditions

15 slide

Temperature is of great importance for seed germination. Seeds of many plants are able to germinate in a fairly wide range of temperatures. However, for each species there are certain upper and lower limits. For most plants, the minimum temperature is 0-5 C, and the maximum is 45-48 C. The optimum temperature for seed germination of many plants is 25-35 C. Conditions for seed germination Cold-resistant plants include rye, peas, and wheat. To heat-loving - melon, cucumber, tomatoes.

16 slide

Seeds of many plants of temperate and cold climatic zones do not germinate without freezing. Therefore, in agricultural practice, stratification is used - keeping seeds in wet sand at low temperatures. This technique accelerates the germination of seeds of many plants. seed germination conditions

17 slide

The fruit is the reproductive organ of angiosperms, providing seed reproduction. Fruit functions: formation, protection and distribution of seeds. Fruits are characteristic only for flowering plants. The fruit is formed from the flower, usually after fertilization. The main role in the formation of the fetus is played by the gynoecium. The lower part of the pistil - the ovary, containing the ovules, grows and turns into a fruit. The fruit consists of a pericarp and seeds, the number of which corresponds to the number of ovules. Fruit

18 slide

Sometimes other parts of the flower (stamens, perianth, receptacle) also take part in the formation of the fetus. Fruit structure: stalk; 1 - exocarp; 2 - mesocarp; 3 - endocarp; 4 - seed. The pericarp, or pericarp, is the wall of the fetus that develops from the wall of the ovary. As a rule, the pericarp makes up the bulk of the fetus. Three layers are usually distinguished in it: exocarp, the outer layer of the pericarp; mesocarp, middle layer of the pericarp; endocarp, the inner layer of the pericarp. Fruit

19 slide

In different fruits, the layers of the pericarp are expressed in different ways. For example, in a drupe (the fruit of a cherry, peach), the exocarp is thin, leathery, the mesocarp is thick, juicy and fleshy, and the endocarp is hard woody (bone). In the hazel nut, the layers of the pericarp are practically indistinguishable. Fruit

20 slide

There is no generally accepted classification of fruits. Distinguish a simple fruit - a fruit formed from the ovary of a single pistil (peas, cherries, poppies); complex, or prefabricated, fruit - a fruit formed from several pistils of one flower (raspberry, blackberry, buttercup). Fruit classification

Angiosperms: 1. They have an organ of seed reproduction - a flower. 2. After flowering, a fruit is formed, in which the seeds are located. 3. Seeds develop inside the fruit, that is, they are protected (covered). 4. A well-developed conducting system, which ensures the rapid movement of substances in the plant.

Lesson objectives: 1. Get to know the structure of the seed. 2. To reveal the structural features of the seeds of monocots and dicots. 3. Develop the ability to work with natural objects, compare them. 4. To form practical skills in seed recognition and seed identification. 5. To carry out environmental, environmental education on the example of the lesson material.

Conclusions: 1. The seed consists of: seed coat, embryo, and contains a supply of nutrients. 2. Embryo - the germ of a future plant. It consists of: germinal root, stalk, kidney and cotyledon. 3. Cotyledons are the first leaves of the plant embryo. 4. Plants that have one cotyledon in the seed embryo are called monocots - these are wheat, corn, oats, onions, etc. 5. Plants that have two cotyledons in the seed embryo are called dicots - these are beans, cabbage, apple trees, peas, etc.

Test "I believe - I do not believe" Surname, name: "+" OR "-" 1. All seeds have two cotyledons and endosperm. 2. Seeds of plants that have one cotyledon are called dicots. 3. Water enters the seed through the seed entrance. 4. Outside, the seed is covered with bark. 5. The supply of nutrients may be in the endosperm. 6. There are two cotyledons in a dicot seed. 7. Cotyledons are part of the embryo. 8. Reserve nutrients are in the stalk 9. Seeds of monocot plants contain one cotyledon. 10. In bean seeds, the cotyledons have the largest mass. The task was checked by (a): Rating: Last name, first name: "+" or "-" 1. The seed peel performs a protective role. 2. Plants of the dicotyledonous class have one cotyledon. 3. The seed coat is part of the embryo 4. The seed of a dicotyledonous plant consists of the seed coat and the embryo 5. In a grain of wheat, reserve nutrients are found in the endosperm. 6. A grain germ contains two cotyledons. 7. The embryo of the seed of dicotyledonous plants contains 2 cotyledons, a root, a stalk, a kidney. 8. The bean seed contains nutrients in the germ. 9. The seed coat of a grain of wheat is easily removed. 10. Seed - the germ of a plant. The task was checked by: Evaluation: After reading the sentences, determine whether the statement is correct or not. If correct, then put "+", if not true, then put "-" I option II option _ _ + _ _ _ _ _ _
Questionnaire "Rate the lesson" 1. Were you interested? 2. Did you learn something new? 3. Was the studied material accessible? 4. Did you understand it? 5. What difficulties arose (what did they not understand)? 6.Your wishes. (answer "no" - 0 points; answer "yes" - 1 point; answer questions 5 and 6 in full)