Answer:
The correct order is dehydration, embed in wax, cut into sections, staining
Explanation:
There are certain proceedings needed to obtain stained sections of vegetable or animal tissues for their microscope observations.
These steps are:
- Obtention of the material: The tissue is cut to an adequate size.
- Fixation: When tissues are extracted from the organism, they suffer autolysis and putrefaction, so they need to be fixated in order to keep their cells in the best state possible. Fixation involves preserving the original morphological and molecular characteristics of the tissue. Fixation avoids autolysis, putrefaction, distortion, and retraction of cells and the tissue that could affect its volume or morphology.
- Dehydration. Once fixated, the fixator must be eliminated and the tissue is dehydrated by using a gradual series of solutions with alcohol in ascendant concentrations. Dehydration must be gradual to avoid tissue deformation.
- Inclusion. To obtain thin cuts that can be observed under the optic microscope, the tissues must be included in a consistent, firm substance, that might be either hydrophilic or hydrophobic. A hydrophobic medium is paraffin wax, that provides hardness and plasticity.
- Cut. The tissue included in wax must be cut in slides or sections thin enough to allow the diffusion and penetration of light. A microtome is used to perform these cuts. When using paraffine for tissue inclusion, the cuts are about 5 to 20 micrometers of thickness.
- Stain. Once the cuts are performed, paraffin wax must be eliminated. This can be done by using an organic solvent. Then the tissue must be stained. Hematoxylin and Eosin are the most common dyes. Animal tissues in general do not have any natural color, so they need to be stained to be observed.
Answer:
b
Explanation:
<em>Let the wild type trait, the silver-white, be represented by </em><em>A</em><em> allele and the mutant trait, the golden color, be represented by </em><em>a</em><em> allele.</em>
Heterozygous wild-type male fish would be Aa
Golden female fish would be aa
Aa x aa
Aa Aa aa aa
2/4 Aa = silver-white
2/4 aa = golden color
<em>Hence, the percent likelihood of golden offspring is </em><em>2/4 or 50%.</em>
The correct option is b.
Answer:
a. Heterozygous individuals may pass on their copy of the disease-causing allele to offspring.
Explanation:
Tay-Sachs, which is a recessive lethal disease ---- Let say the recessive lethal diseases is s
∴ it only results when an individual posses two copies of the diseases-causing allele i.e two copies of the disease will be ss.
Now, when two hetrozygous individuals crossed , it is obvious that each can pass on their copy of the disease-causing allele to the offspring.
Let show an illustration for the above statement.
Let the heterozygous individual be Ts, if Ts cross with another Ts;
we will have:
Ts × Ts
T s
T TT Ts
s Ts ss
the offspring are TT,Ts,Ts,ss
We can now see how the Heterozygous individuals pass on their copy of the disease-causing allele to the offspring (Ts).
Answer:
The correct answer is- A) two, B) yes, the number is the same as monosaccharides.
Explanation:
There are three atoms are present in a molecule of water which includes two atoms of the hydrogen and one atom of the oxygen. The hydrogen atom is two times larger in the number of the oxygen atom in a single molecule of the water.
In monosaccharides, the ratio of the atoms of carbon, hydrogen, and oxygen is 1:2:1 which means one hydrogen atom would be twice in the number of the carbon and oxygen atoms in a single molecule of monosaccharide molecule.
Thus, the correct answer is - A) two, B) yes, the number is the same as monosaccharides.
Answers: 1 .The difference in the brightness of two stars with the same surface temperature is attributable to their sizes.( last choice)
2.Most responsible for the formation of a star is gravitational force.(second choice )
3. Blue ( last choice)
4.
A spinning neutron star that appears to give off radio wave pulses is called a pulsar ( third choice)
5.Greater redshifts in the spectra of galaxies indicate faster speeds ( first choice)
