Câu hỏi:
11/09/2023 441(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.
(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.
(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.
(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulate. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.
Where do protozoans probably live?
Sách mới 2k7: Tổng ôn Toán, Lí, Hóa, Văn, Sử, Địa…. kỳ thi tốt nghiệp THPT Quốc gia 2025, đánh giá năng lực (chỉ từ 110k).
Quảng cáo
Trả lời:
Đáp án A
(1) The protozoans, minute, aquatic creatures each of which consists
Aquatic: sống ở nước
Câu hỏi cùng đoạn
Câu 2:
What is protoplasm?
Lời giải của GV VietJack
Đáp án B
(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm
Câu 3:
To which class of protozoans do the amoebae belong?
Lời giải của GV VietJack
Đáp án C
(1) The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.
Câu 4:
What is the purpose of the large nucleus in the Ciliata?
Lời giải của GV VietJack
Đáp án C
(1) usually a large nucleus that regulates growth but decomposes during reproduction
Câu 5:
Why are protozoans classified as animals?
Lời giải của GV VietJack
Đáp án A
(1) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds
Câu 6:
The word “uniformly” in paragraph 4 is closest in meaning to
Lời giải của GV VietJack
Đáp án A
Uniformly -> in the same way: theo cùng một cách
once in a while: thỉnh thoảng
all of a sudden: một cách bất ngờ
in the long run: sau cùng, rốt cuộc là
Câu 7:
The word “they” in paragraph 3 refers to
Lời giải của GV VietJack
Đáp án A
(1) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they (protozoans) do not live on simple organic compounds
Câu 8:
Which of the following statements are NOT true of protozoans?
Lời giải của GV VietJack
Đáp án C
A: (4) Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified.
B: (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life
D: (4) No doubt, as the technology improves our methods of observation, better models of classification will be proposed.
CÂU HỎI HOT CÙNG CHỦ ĐỀ
Câu 3:
With which of the following topics is the passage primarily concerned?
về câu hỏi!