1.Dễ
What is a tissue?
- AA single cell that has one special job in the body
- BA group of similar cells that work together
- CA structure inside a cell
- DSeveral organs that work together
2.Dễ
What is an adaptation?
- AAny mutation that damages a gene
- BA disease that weakens a population
- CA change an organism makes during its lifetime that it then passes on
- DAn inherited trait that helps an organism survive in its environment
3.Dễ
Trong DNA, adenine luôn bắt cặp với base nào?
- AUracil
- BGuanine
- CCytosine
- DThymine
4.Trung bình
Which statement about identical and non-identical twins is correct?
- ABoth kinds of twin always share all of their genes
- BIdentical twins come from one zygote; non-identical twins come from two
- CIdentical twins come from two eggs that are fertilised by a single sperm
- DNon-identical twins come from one zygote that splits in two
5.Trung bình
Điều gì xảy ra trong phiên mã?
- AMột protein được xây dựng từ thông điệp của mRNA
- BCác amino acid được nối với nhau tại ribosome
- CToàn bộ phân tử DNA được sao chép trước khi phân chia
- DMột bản sao mRNA của gene được tạo ra từ DNA
6.Trung bình
Clostridium tetani grows in deep puncture wounds but is killed by oxygen. How is this bacterium described?
- AAn obligate aerobe
- BA facultative anaerobe
- CA photosynthetic bacterium
- DAn obligate anaerobe
7.Khó
Redi placed meat in open jars and in jars covered with gauze. Maggots appeared only on meat that flies could reach. What did this show?
- AMaggots come from eggs laid by flies, not from the meat itself
- BMeat turns into maggots when exposed to air
- CFlies form from rotting meat, and then they lay eggs on fresh meat
- DGauze produces chemicals that stop meat from rotting
8.Khó
Griffith injected mice with heat-killed harmful bacteria mixed with live harmless bacteria. The mice died, and live harmful bacteria were found in them. What did this show?
- ABacteria can be killed by the immune system of mice
- BThe mice were killed by the dead bacteria alone
- CA substance from the dead bacteria changed the harmless ones
- DHeat makes harmless bacteria become harmful when they are injected
Đáp án
- 1. B · A group of similar cells that work together
- 2. D · An inherited trait that helps an organism survive in its environment
- 3. D · Thymine
- 4. B · Identical twins come from one zygote; non-identical twins come from two
- 5. D · Một bản sao mRNA của gene được tạo ra từ DNA
- 6. D · An obligate anaerobe
- 7. A · Maggots come from eggs laid by flies, not from the meat itself
- 8. C · A substance from the dead bacteria changed the harmless ones
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