![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
Stem structure of scientific dicotyledons The stem structure of dicotyledons: 1. Bark: outer bark 2________ It contains organic matter that can be transported________ 3. Cambium: function:_________ 4. Xylem (xylem): a substance that contains organic matter ______ 5、________ It has the function of storing nutrients
Phloem sieve tube
Phloem is formed outward and xylem is formed inward
4 fiber bundle tube
5 medulla
In order to explore the transportation route of organic matter in plant stems, the scientific interest group designed the following experiments. After a period of time, the bark of a small tree trunk was "circumcised". It was observed that 1) nodule was formed above the branch incision, and no nodule was formed below the incision, and there was a certain degree of shrinkage. 2) the green leaves on the branch above the incision could continue to survive, 3) The root of the plant gradually shrinks. Please help the interest group to analyze the following questions: 1) why the green leaves on the branches above the incision can continue to survive? 2) after a period of circumcision, there is a tumor formation above the incision, which indicates that there is some accumulation above the incision. However, the root from below the incision to the plant gradually shrinks because. 3) according to the knowledge learned, 4) according to the above experimental phenomena, you think that the direction of organic matter transport is. 5) please predict that this small tree will eventually be destroyed
1. Cutting off the bark only cuts off the phloem (sieve tube) which transports nutrients, and the xylem (vessel) which transports water and inorganic salts from the root still works normally, so the leaves can also carry out normal photosynthesis and respiration
2. Organic matter
3. Screen pipe
4. Top down
5. Death due to lack of nutrition in roots
RELATED INFORMATIONS
- 1. The stem and material transportation of plants (1) and (2)
- 2. With the theme of "plants and human beings", write a horticultural composition (about plants cultivating sentiment, anyway, I think so). Or teach me how to write it! It's due on Monday! Another: good plus a reward
- 3. What did man invent from plants? It's plants, not animals
- 4. The material general family has! Come on, don't go through today's 13.50
- 5. Words 500-800
- 6. It's better to add 300 or 400 words with a little bit of prose,
- 7. Questions in brackets: Questions in brackets: 1.We went to London (by plane ) last year ( ) ( ) you ( ) to London last year 2.My father went to bed (at 11:00) yesterday . ( ) ( ) ( ) your father ( ) to bed yesterday 3.They visited (Guilin ) a week ago . ( ) ( ) they ( ) a week ago . 4.We stayed in Tibet (for ten days ) last year . ( ) ( ) ( ) you ( ) in Tibet last yentar 5.He goes to school with (his little sister) every day . ( ) ( ) he ( ) to school with every day ( ) ( ) he ( ) to school with every day 6.Tom (went shopping ) last Sunday . ( ) ( ) Tom ( ) last Sunday 7.They want to go to Tibet (because it’s fantastic) . ( ) ( ) they ( ) to go to Tibet? 8.I came back home (the day before vesterday) . ( ) ( ) you ( ) back home
- 8. Fill in the blanks with the proper form of the given words Fill in the blanks a 1.Where ______ you just now?I _______ in the zoo.(be) 2.Listen,the birds ___________ (sing) in the tree. 3.______ Miss Li ______ (have) a long holiday? 4.My mother usually ______ (cook) at 5 o'clock. 5.What _____ the twins _______ on Sundays?(do) They often ______ (go) to the library. 6._______ Helen like _______ (swim)? Yes,she ______ .Look,she __________ (swim) now. 7.The room is dirty.What ______ you ______ (do) just now? I ______ (throw) the paper on the floor. 8.______ (not) kick the ball. 9.It's the ______ of May.There are _______ students in the playground.(twelve) 10.Last week we ______ (have) a _______ (run) race at school. Fill in the blanks B 1._______ (who) comb is this?It's ______ (she),I think. 2.It's 2:00 in the afternoon.The children __________ (make) a kite. 3._______ you often fly a kite?No,we _______ .(did) 4.Let ______ (we) go and join _______ (they). 5.That girl can ______ (sing) French songs. 6.What ______ (will) you like as a birthday present? 7.What ______ in the basket?There ______ some apples in it.(be) 8.How many ______ (read) rooms are there in this building? 9.Many ______ (child) like ice creams. 10.My sister likes _______ (run) very much. Fill in the blanks C 1.Miss Li lives on the _______ (two) floor in this building. 2.Is that ______ (her) bike?Yes,it's _____ (her). 3.Ma Ming wants to take some _______ (photo). 4.She _______ (study) English well. 5.He _______ (fly) a kite last Saturday. 6.Mr Green is very _______ (excite). 7.These _______ (people) are looking at the moon now. 8.You're _______ (watch) a match in your school now. 9.Mr ______ is in the _______ car.(black) 10.______ you ______ (play) the violin?No,I can't. Fill in the blanks 1.______ the girl like _______ (sit) quietly?Yes,she does. 2.How many _______ (foot) does a monkey have? 3.My sister _______ (have) a lot of beautiful stamps. 4.After school he _______ (help) an old man. 5.Who can help ______ (them) with their English? 6.Yang Ling is a _______ (China) girl. 7.Here are some flowers ______ (four) you. 8.Mary is ________ (write) am e-mail to her friend. 9.He _______ (have) many _________ (strawberry) on the plate. 10.______ he usually have a party at weekends?No,he ______ .(do) Fill in the blanks 1.We often ______ (by) fruit in the supermarket. 2.We are now _______ (live) in the town. 3.I _______ (visit) the farm last Sunday. 4.Helen _______ (pick) many apples on the farm last week. 5.Did you like ______ (milk) cows,Nancy? 6.What _____ you _____ yesterday?We ______ our homework.(do) 7.He ______ (want)to go to the park this week end,but I have no time. 8.Helen often ______ (go) to school by bus. 9.What ______ the students _______ (do) now? They ___________ (play) football in the football field. 10.Where ______ you a moment ago? I ______ in the reading room.(be)
- 9. Ask questions about the contents in brackets (______ ）In brackets: (in the morning) Question:__________ ?
- 10. Question in brackets Linda often （does the shopping) on Sundays. What ____ Linda often ______ on Sundays?
- 11. Which plants are propagated by roots
- 12. The plant propagated by stem is (), the plant propagated by leaf is (), the plant propagated by root is () 1. Begonia, 2. Sweet potato, 3. Chlorophytum, 4. Soybean
- 13. Answers to lesson 1 of science homework a of PEP
- 14. What are the similarities and differences between animals and plants
- 15. Scientific knowledge in Grade Seven It is divided into several units, the first chapter is Star Tour, the second chapter is day and night and four seasons, and the third chapter is earth The fourth chapter is the changing topography, the fifth chapter is the organisms on the earth, the sixth chapter is the main groups of organisms, the seventh chapter is biodiversity, and the eighth chapter is the biosphere on the earth
- 16. The life of plants in the seventh grade Thank you, now! Help
- 17. The leaves of green plants are mostly green and flat, and the color of the upper epidermis is darker than that of the lower epidermis. There are many stomata on the leaf epidermis, which are the channels for the plant to lose water. The distribution of stomata on the upper epidermis is less than that of the lower epidermis? Acceptance in 30 minutes
- 18. Answer the question according to the knowledge of plant classification: plants with roots, leaves, flowers and fruits are () plants, also known as () plants Plants with roots, stems, leaves, flowers and fruits are () plants, also called () plants. Plants with roots, stems, leaves and seeds have no flowers. Plants without fruits are () plants. Plants with only roots, stems and leaves are () plants. Plants with only stems and leaves are () plants. Plants whose organisms are directly composed of single cells or multi cells are () plants
- 19. Angiosperms are classified according to which of the following characteristics () a, B, C, D, flowers and fruits
- 20. The general characteristics of leaf epidermis cells are () A. The cells are colorless and transparent. There is cuticle on the outer wall. B. the cells are half moon shaped and contain chloroplasts. C. the cells are square and compact. D. the cells are cylindrical and contain chloroplasts