Answer:
1)Species are separated from one another by prezygotic and postzygotic barriers, which prevent mating or the production of viable, fertile offspring.
2)Speciation is the process by which new species form.
3) It occurs when groups in a species become reproductively isolated and diverge.
Explanation:
Mutation are two types somatic and germ cell mutation...as there is mutation in germ cell it will alter the normal behavior and produce variation !
random fertilization also causes variation as different setup of genes meets with another different...so chances of variation increases !
and third crossing over is in meiosis when chiasmata forms....so in this two homologous chromosome attach to each other and on separation ... some part exchange so leads to variation !
An animal cell lacking carbohydrates on the external surface of its plasma membrane would likely be impaired in CELL TO CELL RECOGNITION.
Carbohydrates have diverse functions, one of their functions is that they serve as a recognition signal at the surface of cells.
Carbohydrates located on the surface of cells enable cells to recognize and communicate with one another.
B is correct. A tendon will join a muscle to a bone, and a ligament joins a bone to another bone. I think of it this way, partly influenced by my biology teacher:
- The achilles tendon, at the back of your foot, clearly joins foot to calf muscle
- The word ligament comes from 'deligare' in Latin, which roughly means to tie together. A ligament 'ties' two bones together
I hope this helps
