Video Transcript
Which of the following statements
correctly links the grana to the thylakoids? (A) Circular grana come together in
stacks to form a single thylakoid. (B) Disklike structures called
thylakoids form stacks called grana. Or (C) a single thylakoid cell is
formed of multiple grana components.
Let’s review the structures within
a chloroplast to answer this question. Chloroplasts are cell organelles
that are surrounded by two membranes. The inside of a chloroplast is
filled with a fluid matrix called the stroma. The stroma contains many enzymes
along with the DNA of the chloroplast and ribosomes. It also contains disklike
structures called thylakoids. These thylakoids, which are one of
the key terms used in our question, form stacks of around 15 or more disks. A stack of thylakoids is called a
granum or plural grana. This is the other key term that’s
been used in the question.
The grana are interconnected by
thin membranous folds called lamellae or a singular lamella. Within each thylakoid is an aqueous
space called the lumen. So now we know the relationship
between thylakoids and the grana, which is (B). Disklike structures called
thylakoids form stacks called grana.
