MRNA carries a transcript of the needed amino acids to tRNA and then to the rRNA ribosomal component.
I’ve annotated your question and colour coded the answer, (the dotted line represents current bird population) and blue line represents what the population will look love after natural selection
Answer:
within the cartilage divide and secrete new matrix
Explanation:
Chondroblasts also called as perichondrial cells form chondrocytes which are the cells of cartilage. They also secrete the cartilage matrix which forms the cartilage. This matrix consists of collagen, fibers, proteoglycans, hyaluronic acid, water and glycoproteins.
They divide within the formed cartilage too to secrete new matrix. They are called chondrocytes when they become a part of cartilage matrix. Here they grow the cartilage matrix by secreting more extracellular matrix rather than dividing. Once the cartilage formation is completed it is composed 10-20% of collagen fibers, 65-80% of water and rest is made by proteoglycan-hyaluronic acid aggregates.