Answer:
Hemoglobin
Explanation:
Hemoglobin is a protein in red blood cells that carries oxygen throughout the body. With SCD, the hemoglobin forms into stiff rods within the red blood cells. This changes the shape of the red blood cells. The cells are supposed to be disc-shaped, but this changes them into a crescent, or sickle, shape.
The sickle-shaped cells are not flexible and cannot change shape easily. Many of them burst apart as they move through your blood vessels. The sickle cells usually only last 10 to 20 days, instead of the normal 90 to 120 days. Your body may have trouble making enough new cells to replace the ones that you lost. Because of this, you may not have enough red blood cells. This is a condition called anemia, and it can make you feel tired.
The sickle-shaped cells can also stick to vessel walls, causing a blockage that slows or stops the flow of blood. When this happens, oxygen can't reach nearby tissues. The lack of oxygen can cause attacks of sudden, severe pain, called pain crises. These attacks can occur without warning. If you get one, you might need to go to the hospital for treatment.
Answer: B
Explanation:
The way something is arranged enables it to play its role, fulfill its job, within an organism (a living thing). Structure-function relationships arise through the process of natural selection.
Answer:
Explanation:
It can be used to predict the outcomes of genetic crosses. How do geneticists use Punnett squares? They can be use to predict and compare the genetic variations that will result from a cross. Diagram showing the gene combinations that might result from a genetic cross.
Answer:
Laws of stratigraphy help scientists determine the relative ages of rocks. This law states that deeper rock layers are older than layers closer to the surface. An unconformity is a gap in rock layers. They occur where older rock layers eroded completely before new rock layers were deposited.
Explanation:
The study of rock strata is called stratigraphy. The laws of stratigraphy can help scientists understand Earth’s past. The laws of stratigraphy are usually credited to a geologist from Denmark named Nicolas Steno. He lived in the 1600s.
Hope this helps!
Brain-List?
Answer: have true roots, stems, and leaves
may have seeds
may not have seeds
have vascular tissue
Explanation:
some vascular plants have seeds and some do not.
they have vascular tissue such as xylem and phloem
they have true roots, stems, and leaves
