Answer:
The five categories of vertebral column are:
- Cervical
- Thoracic
- Lumbar
- sacrum
- coccyx.
Explanation:
The 26 vertebrae of the spine or vertebral column are classified into five categories based on the structural differences between them. The first category is cervical and is made of seven cervical vertebrae. The spines of cervical vertebrae are shorter than that of others and have bifurcations.
The next category is the thoracic and is made of twelve thoracic vertebrae. Thoracic vertebrae are followed by lumbar region made up of 5 lumbar vertebrae. Spines of thoracic vertebrae are longer and are directed downwards while that of the lumbar vertebrae project towards the posterior region. the sacrum is present below the lumbar region and consists of five fused sacral vertebrae. The last category of spine is coccyx. It has four fused coccygeal vertebrae.
Answer:
keratinocytes
Explanation:
The skin contains various types of cells like melanocytes, keratinocytes and Langerhans cells. The Keratinocytes constitute about 90% of the human skin and are mostly present in the basal skin.
The keratinocytes produce keratin protein which protects the skin and some keratinocytes contain keratohyalin granules which are filled with cysteine-rich and histidine-rich proteins. The keratin and these granules make the skin waterproof.
Thus, keratinocytes are the correct answer.
Answer: genetic variation is a mutation or a change in the sequence of DNA. It can be preserved if that sequence is needed for a species to survive ( evolution). It can also be preserved if that sequence is strong enough to be passed down from mother to child. The mutation can be eliminated if it causes distress to the animal or if it makes the animals chances of survival smaller. If an extra fin on a dolphin helped it to better escape its predator and better obtain food then this trait may stick around because it is beneficial to the species. If the fin cause the dolphin to swim slower then the dolphin may not survive to reproduce or the trait will not pass on.
Explanation:
<span>Fever raises the body's temperature to destroy harmful substances. Would be correct.</span>
Well, I can think of three now; there is binary fission, clone, cross pollination... there are others but at this moment I can only think of those. I can however look it up for you