Answer:
option (a) because....,
Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). ... Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA)
option (b) not because,
Within that centrosome there are two centrioles. And centrioles are physical objects made up of things called microtubules.
option (c) not because....,
Centromere repeats in humans are made up of alpha-satellite DNA, a ∼171 bp sequence or monomer that is iteratively repeated. Alpha-satellite monomers are arranged head-to-tail and organized into repeated arrays called higher order repeats (HORs) that range from 0.2 to 5 megabases (Mb) and are chromosome specific.
not option (d) because...,
Centromere repeats in humans are made up of alpha-satellite DNA, a ∼171 bp sequence or monomer that is iteratively repeated. Alpha-satellite monomers are arranged head-to-tail and organized into repeated arrays called higher order repeats (HORs) that range from 0.2 to 5 megabases (Mb) and are chromosome specific.
hope it becomes helpful to you ☺️☺️
good luck 
 
        
             
        
        
        
The structure and shape of each type of human cell depends on what function it will perform in the body. For example, red blood cells (RBCs) are very small, flat discs, which allows them to easily fit through narrow capillaries and around sharp corners in the circulatory system to deliver oxygen throughout the body.
The elongated shape of muscle cells allows the contraction proteins to line up in an overlapping pattern that makes muscle flexing possible.
And human sperm cells’ structures allow them to “swim” long distances to reach an egg for fertilization
 
        
             
        
        
        
The correct answer is A. Saguaro Cacti, with the scientific name <span>Carnegiea gigantea, </span>which is very significant biotic feature to the Sonoran Dessert's ecosystem. The craziest fact about it is that it can grow up to 40 feet tall! The Sonoran Desert is a North American dessert, also. Some other critical biotic features of this desert include joshua trees, rattle snake, and red-tailed hawk. 
Let me know if you need further info. :)
                  - Dotz
        
             
        
        
        
Answer:
D: It would fizz in acid.
Explanation:
Marble is a limestone & will have an acid reaction that is similar to the limestone from which it was formed.
 
        
                    
             
        
        
        
Answer: The average speed of the zebra during time between 0s and 40s is 34 seconds.