Gravitational attraction between two celestial objects (i think)
The organelle you're looking for should be cholorplasts.
Chloroplasts are double membrane bound organelles, which is important for the process so photosynthesis. The outer membrane is smooth and gives the shape of the chloroplast, while the inner membrane forms sac that contains chlorophyll inside.
Chloroplasts exists in green plants that photosynthesize for energy, and they appear the most in mesohpyll cells, a type of cells in leaf.
Gametes that are motile are often called sperm.
The answer should be allele(s).
Alleles are alternative forms of genes. For example in eye color, there is brown eye allele that produces brown eyes or blue eye alleles that produces blue eyes.
However, note that there may be dominant or recessive alleles. Dominant alleles are always expressed, meanwhile, recessive allele is only expressed when there is no dominant allele existing.
An example is let say brown eye allele is dominant and blue eye allele is recessive. The eye gene is controlled by 2 alleles. If I had one brown eye allele and 1 blue, my eyes will be brown, because brown eye allele is dominant.
Answer:
The spleen acts as a filter for blood as part of the immune system. It also helps fight against certain kinds of bacteria that cause pneumonia and meningitis.
