1. in your body, why do muscle cells and skin cells look and behave differently? (points : 1) they have different genes. their genes are being expressed differently. the same genes are being expressed in both types of cells. there is no similarity in their chromosomes. question 2. 2. which genes are present in your liver cells? (points : 1) all your genes are present in your liver cells. only the genes needed by your liver cells are present in those cells. half the number of genes is present in your liver cells.

1. Their genes are being expressed differently. This is because, in specialized cells such as the ones you've been given, genes can be 'switched on and off' to express only the cells necessary for the function of that particular cell.
2. All genes are present in your liver cells. Every cell in the body contains exactly the same genes, they are just 'switched on and off' or expressed differently in different sorts of cells.

Wetlands form where water and land meet. a lake with a wetland fringe can fill in with decayed plant and animal material to become a wet meadow. a pond can fill in to become a bog or fen. sediment can fill in a river marsh to become a swamp.flooding of coastal lowlands from rising sea levels has created broad coastal marshes that are protected from wave action by barrier islands or reefs. coastal wetlands also form when rivers deposit sediment as they reach the ocean. plants then take root and hold the soil firm against the forces of tides and waves.