Answer:
4 Fe + 3 O₂ → 2 Fe₂O₃
Explanation:
Let's start with the oxygen.
Reactants - 2
Products - 3
What number do 2 and 3 have in common? 6.
Put a 3 in the reactants and a 2 in the products to balance the oxygen.
Fe + 3 O₂ → 2 Fe₂O₃
Now let's look at the iron.
Reactants - 1
Products - 4
Put a 4 in the reactants to balance the iron.
4 Fe + 3 O₂ → 2 Fe₂O₃
The equation is balanced. Hope that helps.
Structurally, DNA and RNA are nearly identical. However, there are three fundamental differences that account for the very different functions of the two molecules. RNA has a ribose sugar instead of deoxyribose sugar like DNA.
His parents were both heterozygous for hyperthermia and had the recessive gene. (hope this helps)
The answer is <span>Fish are ectothermic and lay eggs to reproduce, while mammals are endothermic and give live birth to offspring.
Through the elimination process:
</span><span>* Fish are <u>invertebrates</u> and have scales and paired fins, while mammals are vertebrates and have fur or hair. - Fish are vertebrates!
</span><span>* Fish are <u>endothermic</u> and have gills, while mammals are <u>ectothermic</u> and have lungs. - Fish are ectothermic (cold-blooded), and mammals are endothermic (warm-blooded)!
</span>* <span>Fish have streamlined bodies and <u>three-chambered hearts</u>, while mammals are <u>bipedal</u> and have four-chambered hearts. - Fish have four chambered hearts and not all mammals are bipedal!
This leaves choice: </span><span>Fish are ectothermic and lay eggs to reproduce, while mammals are endothermic and give live birth to offspring. All of this is true, but it should be taken into consideration that some fish give live birth and some mammals lay eggs, but this is the most possible choice among all mentioned.</span>
Answer:
C - Contains the embryonic disk
Explanation:
After an egg is fertilized, it begins to divide into smaller cells, from the 1 cell stage, to 2, to 4 and so on. Then, on the third day, the cells fall within 16-200 cells and it is then called a <em>morula</em>.
On the fifth day, the morula becomes a ball of calls which is now differentiated into an <em>inner cell mass and a trophectoderm</em>. The inner cell mass becomes the <em>embryo</em> as development goes on and the trophectoderm, becomes the <em>placenta</em>.
As development goes on further, the floor of the amniotic cavity is formed by the embryonic disk, a layer of prismatic cells derived from the inner cell mass.
The embryonic disc develops into 3 layers:
There is a major differentiation of cells which gives a template for the origin of development of specific organs of the embryo.
