ｐ.23２章 根や茎のつくりとはたらき１ 根のつくりとはたらきはどのよ

ｐ.23

２章 根や茎のつくりとはたらき

１ 根のつくりとはたらきはどのようになっているのだろうか
根は，土の中にのび，植物の体をしっかりと支えるとともに，地中から水や，水にとけた養分などをとり入れるはたらきをしている。
地中の根のようすは，どのようになっているのだろうか。身近に見られるいろいろな植物の根のようすを調べてみよう。

？ 植物の根は土の中でどのように広がっているのだろうか。


ｐ.24

■主根・側根，ひげ根
タンポポでは太い根から細い根が枝分かれしている。このような太い根を主根，主根から枝分かれした細い根を側根という。主根と側根からなる根はアブラナやエンドウでも見られる。
スズメノカタビラでは太い根がなく，多数の細い根が広がっている。このような根をひげ根という。ひげ根はイネやススキ，ユリなどでも見られる。
このように，根のようすは，植物のなかまによってちがいが見られる。

■根毛
細い根の先端近くをよく観察すると，小さな毛のようなものが多く生えている。これを根毛という。タンポポのような根でもスズメノカタビラのような根でも共通して，根毛が生えている。

考えてみよう
根毛があると，植物にとってどのような点でつごうがいいのだろうか。

根毛は，土の粒の間に入りこんで密着している。また，根毛によって根の土とふれる面積が大きくなり，水や水にとけた養分を吸収しやすくなっている（ 図16 ）。


ｐ.25

２ 茎のつくりとはたらきはどのようになっているのだろうか

ふり返り
小学校６年生で学習した，植物の根・茎・葉にある水の通り道は，どのようになっていたか（ 図17 ）。

？ 根から吸い上げられた水や養分の通り道は，どのようになっているのだろうか。


ｐ.26

■道管と師管
観観察２で着色された部分は，根から吸収した水や水にとけた養分などが通る管で，この管を道管という。
茎の断面を顕微鏡で拡大して観察すると，道管の集まった部分の外側には別の種類の管の集まりがあることがわかる。この管を師管といい，葉でつくられた栄養分が運ばれる管である。このように，茎には植物の体の中で物質を効率よく運ぶために，２種類の管が通っている。


ｐ.27

■維管束
茎をさらによく観察すると，数本の道管と師管が集まって束をつくっていることがわかる。この束を維管束という。維管束の並び方には，ホウセンカやヒメジョオンなどのように，輪のように並んでいるものと，トウモロコシやユリなどのように散らばっているものとがある。
維管束は，根から茎，そして葉へとつながっており，植物が生きていくために必要な物質を運ぶ重要なはたらきをしている。

結果 (英語) 1:

extends in the soil, and function make the work

1 and root structure of stem and p.23

2 chapter roots and root
I wonder is how, along with the support firmly the body of the plant , I have a work to incorporate and water, and nutrients dissolved in water from the ground.
State of the roots in the ground, the wonder is how. Let's examine the state of the root of a variety of plants that can be seen close to.

? How roots of plants wonder widespread in the soil.


P.24

■ fine roots are branched from the thick root taproot, lateral roots, the fibrous root
dandelion. Of lateral root the fine roots branched taproot, from a thick taproot root like this. I also found in peas and oilseed rape roots consisting of the lateral roots and taproot.
There is no thick root in annua, many fine roots has spread. Fibrous root of the root like this. I seen pampas grass and rice, etc. also lily fibrous root.
In this way, the state of the root, the difference can be seen by fellow plant.

■
root hairIf you look carefully near the tip of fine roots, like a little hair is growing much. Root hairs of this. In common in the roots, such as Poa annua in the root, such as dandelion, root hairs growing.

If there is a root hair
consider, would the good but will Tsugo in any respect for plants.

Root hair, is in close contact penetrate between the grains of soil. The area that touches the soil of the root by root hairs increases,Make it easier to absorb the nutrients dissolved in water or water (Figure 16).


The wonder is how

work and make p.25

two stem passage of water that you learned in sixth grade
elementary school Recap, roots and stems, leaves of plants, Did How are (Figure 17).

? Passage of nutrients and water pumped up from the roots, I wonder is how.


Colored pieces in a sieve tube
view observation and 2 p.26

■ The vessel,In the tube, such as nutrients dissolved in water or water that has been absorbed from the roots to pass, that this vessel tube.
If you look to expand under a microscope a cross-section of the stem, it can be seen that there is a set of pipes a different type of the outer portion of assembling vessel. Called the sieve tube The tube is a tube nutrients made in the leaves is carried. Thus, in order to efficiently transport the substance in the body of the plant, two tubes are passed through the stem.


If you look even better p.27

■
stem vascular bundle,It can be seen that you are making a bunch sieve tube and vessel number of this come together. Of vascular bundle this bundle. The arrangement of vascular bundles, some to those such as fleabane and impatiens, are arranged as a ring, while others are scattered such as the lily and corn.
It has led to the leaves and stems, roots, vascular bundle has an important role to carry the material required for the plant to live.

結果 (英語) 2:

p.23

stems and roots Chapter 2 making and working

I wonder how they are making 1 roots and working
root is nobita in the soil and working of molten nutrient, water, or water and taken from the ground as well as support the plant body.
Wonder how how the underground roots, has become. Let's see how the roots of various plants closer to be seen.

？ I wonder how plant roots in soil spreading.


p.24

■ taproot and lateral root and fibrous roots
thin roots branches thick with dandelion root. Thick roots branching from the main root, root said taproot and lateral roots. Taproot and lateral roots found in cruciferous and pea.
No fat in POA annua root, spreading many thin roots. Such root is called fibrous roots. Fibrous roots are seen in rice and Japanese pampas grass, lilies, etc.
Difference seen by unidentified plant how the roots, thus.

■ hairs
Well observed, near the tip of the fine roots with the tiny hair has grown more. This is called root hairs. Root hair grows, common dandelion roots or roots such as POA annua.

Think
in what they are hairs there, succeeds to the plant will do.

Root hairs are entered between the soil particles, closely. In addition, area touches the roots with soil by root hairs is larger,That is easier to absorb nourishment melted to water and water (Figure 16).


p.25

wonder how working with 2 stems are

defrost
? how elementary school, learned in sixth grade and plant roots, stems and leaves the water pathway was supposed (fig. 17).

？ Path of nutrient and water was sucked up from the roots, wonder what have become.


p.26

■ vessels and phloem
observations are colored in 2 piecesIn pipes through the melted water absorbed by the roots or the nutrient vessel said the tube;
Find a collection of different kinds of tubes in part of observing the expanding stem cross-section with the microscope, and of vessels gathered outside. Nurses and tubes made in good, leaf nutrients carried in the tube. To carry substances efficiently in plant body the stem thus, attends a two types of tubes.


p.27

■ vascular
observing the stem even more frequently,You can see there are several vessels and phloem, which makes a bunch of. This bundle is called vascular bundles. Such as Balsam and Fleabane, arrangement of vascular bundles are scattered like that how you arranged in the wheel, corn lilies and and that are.
Doing an important working carry substances to vascular system has led to leaves and stems, roots and plants to live.

結果 (英語) 3:

P 23

2 chapter of the stems and roots and working together with the roots

1 what is working?
is the root, in the soil of plants, as well as the body and firmly support, out of the ground water, and in water and nutrients can have, such as working to get.
the underground as the roots, what is going on about that? a lot closer to cause look at the roots of plants to look it up.

? The roots of the plant in the soil in which they are growing?




p24The main roots, roots, roots
dandelions by the thick thin roots from the root is divided into several branches. This a thick root to the main roots, branching out from the main roots, thin roots roots. The main roots from the roots and the roots that rapeseed and peas.
shortawn foxtail Kata villa has its roots in the thick, not of the many fine roots are spreading. This like roots, root Beard said. Beard, and also enable the roots from Schiphol, lilies, too.
in this way, the roots of the plants, by the mad circle can be seen.


fibrils.near the ends of fine roots and observe the small hair-like many of them are growing. This is terminating. DANDELIONS like roots of sparrows, even Kata villa it a common root, root hair growth.


fibrils let us think about it and how to plant it?

fibrils, climbing into the soil between the grain, it is a tight fit. In addition, terminating the roots come Saturday and increase the surface area,Water and nutrients in the water can have and make it easier to absorb (Figure 16).


p 25

2 of the stem and in making what is working? Looking Back


sixth graders in elementary school I learned in, plant roots, stems and leaves of water on the roadway, which has been (Figure 17).

? From the roots of the siphoned water and nutrient passage is, what is going on about that?




p26 tube and the way the teacher tube
invasive observation 2, the colored part,From the roots that absorb water and water to pass through, such as nutrients can have on the tube, the Tube to Tube down the road.
stem section under the microscope to magnify the road portion of the tube was gathered on the outside of the tube is a different type of show that there is a collection of. This Tube to Tube and good teacher, leaves were made in nutrition that can be transported on the tube. In this way, in the stem of the plant material in the body in order to efficiently carry, two types of tube through.


p 27


the vascular bundle stems, and to get a better look,The number of tube and the way nurses tube stack together, I know that. The stack to vascular bundle. vascular bundle of the area1, boric Seng, and crucian carps® on, and so on, as in, corn, lilies are scattered, and so on.
vascular bundle, stems from the roots, and connected to the leaves, plants are required to continue living substances that carry important work.



C.