"Blooming and Fruiting of Plants" PPT courseware

Description

"Blooming and Fruiting of Plants" PPT courseware

Part One Content: The Composition of Flowers

corolla

The crown is made of petals.

Different types of flowers have different sizes, colors and numbers of petals.

calyx

The calyx is the part that supports the petals and is used to protect the flowers before they bloom.

stamens

Stamens grow in the middle of the flower and are the male sexual organs of the flower.

It is composed of anthers and filaments, and its main function is to produce pollen.

Flowering and fruiting of plants PPT, part 2 content: Discussion:

1. As a reproductive organ, which part of the flower will develop into a fruit in the future?

2. Which structures of flowers are most important for plant reproduction?

Explore further:

Suppose a flower's pistil is eaten by a pest, will the flower still develop into a fruit?

summary

Flowers are composed of receptacles, sepals, petals, pistils, and stamens, among which pistils and stamens are the main structures of flowers.

Think about it: How do these structures relate to the formation of fruits and seeds?

Flowering and fruiting of plants PPT, part 3: Types of fruits

(1) Classification based on the structure of flowers and fruits

1. Depending on whether structures other than the ovary are involved in the formation of the fruit: true fruit and false fruit

2. According to the number of pistils in the flower:

Monocarp: A fruit with only one pistil in the flower.

Aggregated fruit: There are many free pistils in one flower, and each pistil later forms a small fruit, gathered on the same receptacle. Lotus, strawberry, raspberry, etc.

Polyflora fruit: The fruit develops from the entire inflorescence, and the inflorescence is also part of the fruit. It is also called inflorescence fruit or compound fruit such as mulberry, pineapple, fig, etc.

(2) According to the properties of the peel when the fruit matures:

1. Flesh fruits: Those with thick flesh are called flesh fruits;

Depending on the origin and nature of the peel, fleshy fruits fall into the following categories:

(1) Berries: Berries are the most common type of fleshy fruit. Except for a few layers of cells on the surface, the peel is fleshy and juicy and contains many seeds, such as grapes, tomatoes, persimmons, etc.

(2) Drupe: usually developed from a single pistil and containing a seed. The peel is obviously divided into three layers. The exocarp is membranous and consists of the ovary epidermis and several layers of cells under the epidermis; the mesocarp is juicy and juicy; and the endocarp is Lignified, hard, and wrapped around the seeds. Such as peach, plum, plum, apricot and other fruits.

(3) Pome: The flowers of the lower part of the ovary are formed. The fruit is formed by the healing of the flower tube and carpel parts and is a false fruit. There is no clear boundary between the exocarp, mesocarp and receptacle. The endocarp is composed of lignified thick-walled cells, so it is relatively clear and obvious. Pears, apples, etc.

2. Dried fruits with dry peel and no juice are called dried fruits.

According to whether the peel cracks when ripe, it is divided into cracked fruit and closed fruit.

(1) Fruit cracking: When the fruit matures, the skin will split on its own and can be divided into the following types:

① Pod: It develops from a single carpel. When mature, the skin splits along the dorsal and ventral sutures, such as soybeans, peas, broad beans, etc.

② Fruit: It develops from single carpel or detached carpel, and only one side cracks when mature. There are fruits that crack along the ventral seam of the carpel, such as sycamore, peony, peony, star anise, etc. There are also cracks along the back seam, such as magnolia, magnolia, etc.

③Capsule (: developed from the compound pistils of the connate carpels, with an ovary

Chamber or multi-chamber, with many seeds in each chamber. When mature, it cracks in three ways: interventricular cracking, perforal cracking, and peripheral cracking.

④ Silique: developed from a pistil composed of 2 carpels. A false septum grows inward from the conjuncture of the carpel edges, dividing the ovary into 2 chambers. When the fruit matures, it splits and falls off along the 2 ventral sutures, leaving only the false septum, and the seeds are attached to the false septum. Cruciferous plants have many such fruits. The siliques are long and slender, with a large length-to-width ratio, and are called long siliques, such as radish, cabbage, etc.; the length-to-width ratios are almost equal, and are called short siliques, such as shepherd's purse, cabbage, etc.

(2) After mature fruits, the peel of closed fruits does not crack, and they can be divided into the following types:

①Achene is a small closed fruit composed of 1-3 carpels; the pericarp is hard and has 1 seed. The pericarp and seed coat are easy to separate. Such as Pulsatilla (composed of 1 carpel), sunflower, dandelion (composed of 2 carpels), buckwheat (composed of 3 carpels), etc.

②Caryopsis: The pericarp is thin and leathery, containing one seed. The pericarp and seed coat are not easy to separate when they heal. The fruit is small and is a unique fruit type of gramineous plants such as rice, wheat, and corn.

③ Samara is an achene in nature, and its peel extends into a wing shape, which is conducive to wind spread, such as elm, maple, ailanthus and other plants.

④Nuts: The exocarp is hard and woody, with one seed. Mature fruits often have the original inflorescence involucre attached, which is called a cupule, such as oak, hazel, chestnut and other fruits.

Keywords: Jiangsu Education Edition seventh grade biology PPT courseware free download, plant flowering and fruiting PPT download, .PPT format;

For more information about "The Life of Green Plants, Flowering and Fruiting of Plants" PPT courseware, please click on the "Life of Green Plants ppt, Flowering and Fruiting of Plants" ppt tag.

"Blooming and Fruiting of Plants" PPT:

"Blooming and Fruiting of Plants" PPT Part One Content: Classroom Thinking Thinking: What is the meaning of plant flowering? Which part of the flower will develop into fruit in the future? Which structures in flowers are most important for plants to reproduce? 1. Flower structure stamens ..

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Update Time: 2024-09-08

This template belongs to biology courseware Jiangsu Education Edition Seventh Grade Biology Volume 1 industry PPT template

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