Answer:
B) Na+
Explanation: Na+ molecule is polar, oxygen and carbon dioxide are nonpolar molecules. The cell membrane is a <em>phospholipid bilayer</em> made up of lipid molecules with polar and nonpolar ends. Since it is a bilayer, two phospholipid layers are arranged, one on the other in such a way that one faces the back of the other. The non polar ends are away from outside and inside of the cell, while the polar ends faces towards all the molecules inside and outside the cell.
Since polar-polar molecules repel each other, Na+ can't pass through the cell membrane easily. So it uses the proteins attached the cell membrane inside and outside to transport such molecules by using energy in terms of ATP.
1. Arteries : Carry's blood away from the heart.
2. Veins : Carry's blood back to the heart.
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3. Capillaries : exchange of materials and gases between the cell and vessel takes place here.</span>
It is used by every living cell.
Cellular respiration is a process of combining oxygen with foodstuff molecules, diverting the chemical energy in these substances into life-sustaining activities and discarding, as waste products, carbon dioxide and water.
The egg is produced by the female part the "ovaries", then sent down to the fallopian tube during sexual reproduction which then where the sperm and egg meet which then forms a baby that grows in the uterus for 280 days or 40 weeks. :)
Answer:
The correct answer is "strengths: inexpensive, easy to culture, short life cycle, large number of offspring; weaknesses: invertebrate model, some diseases such as immunological cannot be modelled, anatomical features are very different from humans"
Explanation:
The fruit fly <em>Drosophila melanogaster</em> is one of the most used animal model for genetic and biomedical studies. There are many advantages of using Drosophila as model, including that it is very inexpensive to handle, it is easy to culture, it has a short life cycle allowing to observe the changes in phenotype very quickly and its large number of offspring allows to include several repetitions per trait in a study. However, there are some weaknesses of using Drosophila to study human biology. First, obviously the fruit fly is very different from humans, it is an invertebrate and its anatomical features are very different, which makes impossible to model some disorders such as immunological diseases.
