7.1 Chromosomes, Genes and DNA

The part of the cell that controls its activities is (a)   .

• Mitochondria
• Cytoplasm
• Nucleus
• Cell wall

What structures are found in the nucleus that control cell activities?

• Ribosomes

• Chromosomes

• Lysosomes

• Chloroplasts

When do chromosomes become visible under a light microscope?

• During cell division

• During photosynthesis

• During protein synthesis

• During respiration

What is used to make chromosomes visible under a microscope?

• Heat

• Special stains

• Magnification

• Light filters

What kind of chromosomes are found in fruit flies, making them easier to study?

• Circular chromosomes

• Giant chromosomes

• Mini chromosomes

• Dense chromosomes

How many chromosomes are found in human cells?

• 8

• 23

• 46

• 40

How many chromosomes are found in fruit fly cells? (a)  

• 46
• 8
• 23
• 40

Which organism has 40 chromosomes in its cells?

• Humans

• Fruit flies

• Mango trees

Match the following methods of chromosome numbering with their descriptions.

• Chromosomes are organized from the largest to the smallest.

• By the sequence of their genes

• Chromosomes are arranged based on the order of their genetic information.

• By their size, from longest to shortest

• Chromosomes are classified according to their structural form.

• By their color

• Chromosomes are identified based on their staining properties.

• By their shape

How many copies of each chromosome do humans have?

• One

• Two

• Three

• Four