Scheda di esercizi di Biologia per i test di ammissione a infermieristica con soluzioni

Quanti cromosomi ha una tipica cellula somatica umana?

1. A92
2. B23
3. C44
4. D46

How many strands does an RNA molecule usually have?

1. AFour
2. BThree
3. COne
4. DTwo

In which stage of the cell cycle does a cell spend most of its time?

1. AAnaphase
2. BInterphase
3. CMetaphase
4. DProphase

Why is a buffer system important in blood?

1. AIt resists changes in pH
2. BIt makes the blood clot faster
3. CIt raises the blood glucose level
4. DIt carries oxygen to the tissues

Why do the palisade cells near the top surface of a leaf contain many chloroplasts?

1. AThey carry sugars from the leaves down to the roots
2. BThey protect the leaf from insects and strong winds
3. CThey get the most light and do most of the photosynthesis
4. DThey store most of the plant's water for dry periods

Clostridium tetani grows in deep puncture wounds but is killed by oxygen. How is this bacterium described?

1. AA facultative anaerobe
2. BAn obligate aerobe
3. CAn obligate anaerobe
4. DA photosynthetic bacterium

Why is one new DNA strand made in short pieces (Okazaki fragments) during replication?

1. AThe lagging strand is made of RNA instead of DNA, so it must be built in pieces
2. BDNA polymerase works only 5' to 3', and the strands are antiparallel
3. COnly half of the DNA needs to be copied
4. DHelicase cuts that strand into pieces before copying

The field of view of a microscope is 0,5 mm wide. About 10 cells fit across it in a line. What is the approximate width of one cell?

1. A500 µm
2. B0,5 µm
3. C50 µm
4. D5 µm