1.ง่าย
What is the cytoplasm?
- AThe space between two neighbouring cells
- BThe fluid found only inside the nucleus
- CThe jelly-like contents between the membrane and nucleus
- DThe stiff outer layer of cellulose that surrounds a plant cell
2.ง่าย
What does DNA replication produce?
- ATwo identical DNA molecules
- BOne mRNA molecule
- CA new protein
- DFour different DNA molecules
3.ง่าย
Which protein carries oxygen in red blood cells?
- ACollagen
- BKeratin
- CHaemoglobin
- DInsulin
4.ปานกลาง
What is the role of cholesterol in animal cell membranes?
- AIt keeps membrane fluidity stable as temperature changes
- BIt carries glucose molecules across the membrane into the cell
- CIt forms a rigid wall around the cell
- DIt stores the cell's genetic information
5.ปานกลาง
What does it mean that a person's blood is Rh negative?
- ATheir red cells lack the A and B antigens
- BTheir red cells lack the RhD antigen
- CTheir plasma has no antibodies at all
- DTheir red cells carry extra RhD antigen
6.ปานกลาง
เหตุใดแบคทีเรียแกรมบวกจึงติดสีม่วงในการย้อมแกรม
- Aมีคลอโรฟิลล์
- Bไม่มีผนังเซลล์เลย
- Cผนังบางถูกหุ้มด้วยเยื่อชั้นนอกที่อุดมด้วยลิพิด
- Dผนังเพปทิโดไกลแคนหนาจับสีย้อมสีม่วงไว้
7.ยาก
A man has Klinefelter syndrome (XXY). Which error most likely produced it?
- ACrossing over between chromosome 21 and the X chromosome
- BNondisjunction of the sex chromosomes during meiosis in a parent
- CExtra mitosis in the zygote after fertilisation
- DA frameshift mutation in one of the genes on the father's Y chromosome
8.ยาก
Mature human red blood cells have no nucleus and no mitochondria. What follows from this?
- AThey cannot divide and make their ATP by glycolysis only
- BThey keep making new haemoglobin throughout their life
- CThey make ATP by aerobic respiration using the oxygen they carry
- DThey live longer than almost all other body cells
เฉลย
- 1. C · The jelly-like contents between the membrane and nucleus
- 2. A · Two identical DNA molecules
- 3. C · Haemoglobin
- 4. A · It keeps membrane fluidity stable as temperature changes
- 5. B · Their red cells lack the RhD antigen
- 6. D · ผนังเพปทิโดไกลแคนหนาจับสีย้อมสีม่วงไว้
- 7. B · Nondisjunction of the sex chromosomes during meiosis in a parent
- 8. A · They cannot divide and make their ATP by glycolysis only
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