ورقة عمل الأحياء لامتحانات القبول في التمريض مع الإجابات

Which enzyme unwinds the DNA double helix and separates the two strands for copying?

1. ALigase
2. BLipase
3. CHelicase
4. DAmylase

In an enzyme reaction, what is the substrate?

1. AThe part of the enzyme that changes shape
2. BThe gene that codes for the enzyme
3. CThe product released at the end
4. DThe substance that the enzyme acts on

What is homeostasis?

1. AChanging a species over many generations
2. BKeeping a stable internal environment
3. CBreaking down food for energy
4. DMaking identical copies of a cell

Which is the correct way to write the scientific name of the gut bacterium?

1. AEscherichia Coli
2. BEscherichia coli
3. Ccoli Escherichia
4. DEscherichia Coli

Red-green colour blindness is X-linked recessive. A colour-blind woman (XᵇXᵇ) has children with a man with normal colour vision (XᴮY). What fraction of their sons is expected to be colour-blind?

1. AOne half
2. BAll
3. COne quarter
4. DNone

Which DNA bases are purines?

1. AAdenine and guanine
2. BCytosine and guanine
3. CAdenine and thymine
4. DCytosine and thymine

Cyanide stops mitochondria from making ATP. Which process in the affected cells would stop first?

1. AFacilitated diffusion of glucose down its gradient
2. BSimple diffusion of oxygen into the cell
3. CPumping of Na⁺ and K⁺ by the sodium-potassium pump
4. DOsmosis of water across the membrane

Why does cooking oil not mix with water?

1. AOil molecules are polar and repel the charged ends of water molecules
2. BWater molecules are nonpolar and avoid each other
3. COil is denser than water and sinks
4. DOil molecules are nonpolar and cannot form hydrogen bonds with water