I believe it is D. More African elephants today naturally lack tusks compared to the elephant populations 100 years ago, because big game hunters sought elephants for ivory.
Answer:
B, C, Dand E are all correct
Explanation:
Why B is correct- The cell membrane, also known as the plasma membrane, is a double layer of lipids and proteins that surrounds a cell and separates the cytoplasm (the contents of the cell) from its surrounding environment. It is selectively permeable, which means that it only lets certain molecules enter and exit.
Plants, animals, and bacteria have a cell membrane. Why d is correcect
Why C is correct- The cell membrane is not a solid structure. It is made of millions of smaller molecules that create a flexible and porous container. Proteins and phospholipids make up most of the membrane structure.
Why E is correct- The plasma membrane is primarily composed of phospholipids arranged in a bilayer, with the hydrophobic tails on the interior of the membrane, and the hydrophilic heads pointing outwards
Why A Is Not correct- It is very fragile and its role is to hold the cell together and to help control what substances can get in and out. It is partially permeable, allowing only some substances to pass through it. The membrane has a complex structure consisting of a phospholipid bi-layer and different types of proteins.
<span>The space-filling model of a hydrogen molecule would be something like OO , two circles stuck to each other, even squished a little bit. The model for carbon dioxide would be like OOO, with the two circles on the sides a little bigger and squished into the middle circle. </span>
The answer is c because the other are soft
The answer is False.
Although, there are some evidence that suggests that species from million years ago possessed both gills and lungs. For example is the Acanthostega Gunnari, one of the oldest species discovered with four limbs. The creature is a salamander-like creature found in Greenland hundreds of million years ago. Although the specie can walk on land but the finding characterized the creature primarily as a fish.
