It’s the first one!
compact bone is a dense bone with a bony matrix that is solidly filled with arya if ground substance and inorganic salts, leaving only tiny spaces (lacunae) that contain osteocytes, or bone cells. Immature compact bone DOES NOT CONTAIN OSTEONS and has a woven structure.
hope this helps!
Basically the seed contains 2 parts, the testa, which is the seed coat that protects the seed and cotelydon, which is the inside of the seed, containing the radical and plumle.
for seed to germinate, we need 3 basic conditions,
warmth, it is the suitable temperature for seed germination, it can influence the activity of enzymes. providing a optimum temperature
water, to soften down the testa so that the shoot can break out from the testa
and oxygen, for aerobic respiration
.
If these conditions are absent, the seed may be in the state of dormancy. where is won't germinate until it meets the suitable conduction.
after that, the enzyme will digest the nutrient inside the seed and provide amino acid, which is necessary to seed germination. and meanwhile the aerobic respiration provides energy, so that the plumlecan shoot out, and be the shoot of the plant.
and then until it grows leaves, it'll start to complete photosynthesis, instead of using the nutrients inside the cotelydon.
May not be right, but because of Oxygen and the growing of new skin? We rub our skin without noticing and it will become frail and rub off, creating new skin
