Out of the 12 pairs of ribs in rib cage of human, how many ribs are true and false, respectively?

Options

A. 7, 3
B. 14, 6
C. 7, 4
D. 14, 4

Answer

To solve the question regarding the number of true and false ribs in the human rib cage, we can follow these steps:

### Step 1: Understand the Structure of the Rib Cage
The human rib cage consists of 12 pairs of ribs. This means there are a total of 24 ribs.

### Step 2: Identify True Ribs
True ribs are defined as the ribs that are directly attached to the sternum (breastbone). In humans, the first 7 pairs of ribs are classified as true ribs.

### Step 3: Identify False Ribs
False ribs are those that are not directly attached to the sternum. In humans, the last 5 pairs of ribs are considered false ribs. However, these can be further categorized:
- The 8th, 9th, and 10th pairs of ribs are known as "vertebrochondral ribs" because they are indirectly connected to the sternum via the cartilage of the 7th rib.
- The 11th and 12th pairs are known as "floating ribs" because they do not attach to the sternum at all.

### Step 4: Count True and False Ribs
From the above information:
- True ribs: 7 pairs (1st to 7th)
- False ribs: 5 pairs (8th to 12th)

### Final Answer
Therefore, the number of true ribs is 7 and the number of false ribs is 5.