Предмет: Биология, автор: angelina719

устойчивы ли пресные водоемы?

Ответы

Автор ответа: OXSERG2010

Вывод. Важно не нарушать количественное соотношение различных видов животных и растений в пруду, тогда всем хватит пищи. Почему же сообщество развивается и не погибает?

Оно устойчиво благодаря цепям питания. И чем разнообразнее цепь питания, тем она более устойчива.

Важнейшую роль в жизни водоема играют факторы неживой природы: свет и температура.

Свет нужен для нормального роста растений. У затененного растения побеги поблекнут и станут длиннее и тоньше. Чтобы питаться и выделять кислород, необходим солнечный свет.

Тепло – также необходимое условие жизни водоема. Температура очень важна. Например, когда вода становится холодной, то лягушки прячутся на дно, а рост растений прекращается еще раньше, что влияет на многих животных.

Предыдущий вопрос

Следующий вопрос

Похожие вопросы

Предмет: Математика, автор: utelovadamira016

Ааааааааааааааааааааа́а4,46; обыкновенный дроби

6 лет назад

Предмет: Английский язык, автор: lili4355

помогите по английскому
Task 1. Read the text. Match the paragraph with the definitions.

A. Travel is something that people do every day. It is very difficult to avoid the need to travel. It may be a trip to school, university or to work. Travelling can often take a long time, especially when great distances need to be covered. People often enjoy travelling abroad for holidays. However, for some people travelling is not fun at all. Some people suffer from travel sickness. This means that they will become unwell each time they travel.
B. Travelling can be either affordable or costly. It often depends on how far you want to travel and the choice of transport. Using a bicycle will not cost anything as you power it by using your legs. However, the use of a bicycle can be hard work and can take a lot of time to travel long distances. Cars and motorcycles are faster modes of transport, but they are more expensive to use as gasoline is needed for them to work. It can usually be assumed that the longer you wish to travel, the more expensive and time consuming it will be.
C. The use of a plane is necessary for people wanting to travel very long distances. A pilot will fly a plane from an airport for many thousands of miles to take people to places far away. Although traffic is rarely a problem for airplanes, it can take a lot of preparation to travel by plane. People often need to arrive at the airport three hours prior to departure.
D. A train is another mode of transport which is ideal for travelling long distances within the same country, or between countries which are connected by land. A train driver will stop at train stations on route to allow passengers wishing to proceed to the scheduled destination to board the
train.
E. A number of destinations can be travelled to by using the sea. People often depart from a harbour in a ferry which is driven by a captain. If the journey is a long distance, people may choose to sleep on the ferry while they wait to arrive at their destination. Some people choose to go on a cruise for their holiday, which would involve stopping at many different city ports for a short amount of time. People who need to travel short distances may choose not to use any transport at all. People often rely on their legs to take them to places nearby and they walk. This is often encouraged as certain modes of transport have been said to produce harmful emissions and damage the environment.

1. This paragraph describe transport which doesn’t cost money_____
2. This paragraph describe why any people don’t enjoy travelling________
3. This paragraph describe mode of transport which is ideal for travelling between countries connected by land.________
4. This paragraph describe the fastest transport.________
5. This paragraph describe the mode of ecological transport.__________

II. Write a descriptive essay about piece of art. Use writing guide.

Think and plan:

Who was the work created by and when?
What does the work of arts show?
What art movement is this typical of?
What is typical of this art movement?
When was the work first exhibited?
When was it last sold and where is it kept?

Write
Paragraph 1: The work of art
….. was painted/made by …..
Paragraph 2: The art movement
This type of work is typical of …..
Paragraph 2: History of work
….. was first exhibited in …..
Check
Past and present passive

СРОЧНО ПОЖАЛУЙСТА

6 лет назад

Предмет: Математика, автор: moldirzajlaubaeva6

ПОЖАЛУЙСТА помогите срочно

6 лет назад

Предмет: Математика, автор: hiphop2201

(2/3-1/9): 5/6
2 целых 7/8*5 целых 1/3: 3 целых 5/6
6 целых 2/3:(4/5-7/20)

9 лет назад

Предмет: Алгебра, автор: baby22

1)5a^2-5-4(a-1)^2 =
2)2(x+y)^2+x^2-y^2 =
3)a^4+ab^3-a^b-b^4=
4)(x-y+4)^2-x^2+2xy-y^2=
5)x^3+y^3+2xy(x+y)=
6)49(y-4)^2-9(y+2)^2=
Решите пожалуйста!!!Очень нужно!!!!!

9 лет назад