ECNU Edition VII Science Midterm Practice Paper 1 .

d I'm not very sure about this question Go back and flip through the biology book There must be a detailed explanation I only deducted two points for the biology college entrance examination The reason is that I copied the book three times before the college entrance examination Copy word for word and copy the picture well.

dThis question is about the passive transport of cells, and the cell fluid will be balanced according to the amount of concentration, and the conditions for the active transport of cells will passively flow to the place where the concentration is high, and the d option is to use the evaporative heat absorption of alcohol to cool down, which is different from other options.

b. Same as above: The greater the concentration, the less cell fluid, and the greater the cell fluid can read.

a. Use the elimination method b. I don't really know about flood pollutants, but I intuitively exclude this option c. The stomata will not be blocked by sediment The stomata are too small and the sediment is too large to block d. Enhance light instead of enhancing photosynthesis Light is based on the sun Except for geographical factors, it cannot affect the light Only a is the most likely Plant branches are thinner and may lodging due to heavy sediment pressure And after the flood, the roots are not firmly rooted and are more prone to lodging.

A basic biological knowledge that can be drawn is basically a plant cell wall.

d, because there is no picture, so I do this question by imagination Ask the section of the descent There are leaves and light, and it must lose less weight, because photosynthesis will cancel out some of the energy substances consumed by respiration, that is, sugars, so the reason for the decline is respiration or transpiration, and this is specifically to see which side has leaves at the bottom, and the one that has fallen must not have fewer leaves.

I've been out of high school for two years, and the questions are all from memory, and the explanations are not very clear, and they are not professional, and they are all in the vernacular, and I hope to accept the answers.

A temperature beam tremor digging degree increased, rubber nucleus d, carbonic acid decomposition.

2. In the process of dissolving substances, some are endothermic such as (salt cave is built in water), and some are exothermic such as (sulfuric acid dissolved in water).

:9 35.Brown petrel swordfish 36Mass 450N 49kg 37Gravity is always 39 straight downVariable speed movement in the middle of the self-counting. 41 .500 1000 times 10 equals 5n

Question 29: When the reaction occurs in the experiment: NaCO3+2HCl=2NaCl+H2O+CO2, so with the addition of hydrochloric acid, the experimental phenomenon in the BC section is that you can see that there are bubbles generated, you can look at the coordinates of the figure, the horizontal and vertical coordinates are the quality of hydrochloric acid and the mass of the solution, so there is a reaction at point B, that is, there are bubbles, then due to the release of carbon dioxide, the mass of the solution is in a relatively stable process with the increase of hydrochloric acid, When the reaction is complete, the mass of the solution increases relative with the addition of hydrochloric acid.

Before point B, since hydrochloric acid is added dropwise, it is preceded by a neutralization reaction with sodium hydroxide, and at point B, a reaction with sodium carbonate begins, and bubbles are generated.

7th and 8th grade science contest questions.

2.The total resistance of the school's lighting circuit, which is maximum when the lights are off.

Question: Why? I checked the others, and said that it is infinity because there is no current, but the resistance is related to the inside, right, and it will be affected by the current? (Explain).

That's because the resistance wire heats up when the lamp is connected, causing the resistance to decrease.

So the resistance is the greatest when it is disconnected.

Isn't this taking off your pants and farting?! That's! Put it in a beaker and call it over?! Also scientific, contrary to the principle of life, shit logic. These 2B competition questions really hurt the thinking of Chinese students.