请根据生物进化历程示意图，分别写出植物和动物进化的大致历程。
(1)在生理上，动物类群①的繁殖方式最主要的特征是 ；植物类群③在繁殖方式比植物类群④高等的主要表现是 。
(2)最早的陆生动物是 动物，真正的陆生脊椎动物是 动物，恒温动物中更为高等的类群是 动物。
(3)在分类上，该进化树的两大主干代表的分类等级是 。②是最高级的植物类群，是 植物。对②中的各种植物进行分类，往往把 作为最重要的分类依据。
(4)在进化上，与单细胞动物亲缘关系最近的生物类群是 ___，从图中可以看出生物进化的总体趋势是_________、__________、__________。
(1)胎生、哺乳 用种子繁殖
(2)节肢 爬行 哺乳
(3)界 被子 花、果实、种子
(4)腔肠动物 简单到复杂 低等到高等 水生到陆生
| 阅读理解。 |
| Talking on a mobile phone is expensive, so a lot of people send text messages. Text messages are much cheaper by making the words shorter. You can do this by taking out "unimportant" letters in the words and using numbers instead of words (2=to, 3=free, 4 = for, 8 = ate, so, etc. ). You can also keep a way from using punctuation. Here is an example: Do u wnt 2 g 2 th cnma tnit? (Do you want go to the cinema tonight?) What do you think these text messages mean? Whr hv U bn? Iv bn wing hrs fr a cll. Im hm nw, why nt gv me a cll. I gt a txt mssge frm my frnd. Shes hvng a prty on Strdy. Mobile phone users have developed a group of symbols to show how they feel. They are called emoticons, and there are some examples below. To read an emoticon, you have to look at it sideways. For example, if you say something in a text message that is a joke, you can follow it with a smiling face. Like this : Why didt you call me? I'm so sad.－ (Here are some others. Can you think of text messages where you could use them? -) laughing, -( sad, -< really sad, -o shocked, -v shouting, | . | asleep, 8－| , surprised, /\-o bored. |
1. Why are text messages popular? |