Answer:
periosteum ----> dense irregular connective tissue
Explanation:
- The periosteum is a dense fibrous membrane that covers the surfaces of bones. 
The periosteum consists of two layers-
     1. Outer fibrous layer 
     2. Inner cellular layer
- It is mainly composed of dense irregular connective tissue along with a layer of simple squamous epithelium.
- The function of periosteum is to cover the surface of all the bones except those surfaces that are covered with cartilage such as joints and tendons and ligaments. 
 
        
             
        
        
        
Active transport is the homeostatic process that moves particles against a concentration gradient.
        
                    
             
        
        
        
Answer:
12 molecules of ATP can be made from one molecule of acetyl CoA.
Explanation:
If one molecule of acetyl CoA enter TCA cycle then it result in the formation of 3 molecules of NADH,1 molecule of FADH2 and 1 molecule of GTP that is equivalent to 1 molecule of ATP.
                         Now the reducing equivalent such as NADH and FADH2 enters electron transport chain and get oxidized to regenerate NAD+ and FAD along with ATP. 1 molecule of NADH produces 3 molecules of ATP whereas 1 molecule of FADH2 produces 2 molecules of ATP.
                So that net gain of ATP is given below 
3 molecules of NADH = 9 molecules of ATP
1 molecule of FADH2 =2 molecules of ATP 
1 molecule of GTP = 1 molecule of ATP 
As a result total 12 molecules of ATP is by the oxidation of 1 Acetyl CoA  by TCA cycle .
 
        
             
        
        
        
Answer:
guard cells
Explanation:
they control the opening and closing of the stomata