1.Dễ
Which pigment absorbs light energy for photosynthesis?
- AChlorophyll
- BKeratin
- CMelanin
- DHaemoglobin
2.Dễ
Base nào có trong RNA nhưng không có trong DNA?
- AUracil
- BAdenine
- CThymine
- DGuanine
3.Dễ
What is endocytosis?
- AMoving water across the membrane by osmosis
- BSplitting the cytoplasm after the nucleus divides
- CReleasing material from the cell by fusing vesicles with the membrane
- DTaking material into the cell by folding the membrane around it
4.Trung bình
Which statement about Archaea is correct?
- AThey are a type of virus
- BThey are prokaryotes, and many live in extreme environments
- CThey are multicellular plants
- DThey are eukaryotes that have a nucleus and membrane-bound organelles
5.Trung bình
Drugs against fungal infections often cause more side effects than drugs against bacteria. Why?
- AFungi reproduce only by binary fission
- BFungi have no cell membrane for drugs to act on
- CFungal cells are eukaryotic, like human cells
- DFungi are much smaller than bacteria
6.Trung bình
Why is a buffer system important in blood?
- AIt resists changes in pH
- BIt raises the blood glucose level
- CIt carries oxygen to the tissues
- DIt makes the blood clot faster
7.Khó
Paper discs with antibiotics X, Y and Z are placed on a plate covered with bacteria. The clear zones around them are 2 mm, 15 mm and 0 mm wide. What is the best conclusion?
- AZ is most effective, because no bacteria grew under the disc
- BAll three are equally effective against these bacteria
- CY is most effective, and the bacteria are resistant to Z
- DX is most effective, and the bacteria are resistant to Y
8.Khó
The coding part of an mRNA is 900 bases long, including the start codon and the stop codon. How many amino acids are in the protein?
- A298
- B299
- C300
- D900
Đáp án
- 1. A · Chlorophyll
- 2. A · Uracil
- 3. D · Taking material into the cell by folding the membrane around it
- 4. B · They are prokaryotes, and many live in extreme environments
- 5. C · Fungal cells are eukaryotic, like human cells
- 6. A · It resists changes in pH
- 7. C · Y is most effective, and the bacteria are resistant to Z
- 8. B · 299
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