The two chromatids of a duplicated chromosome are held together at a region of DNA called the centromere. Centromeres are the attachment points for microtubules, which are responsible for the guiding the movement of chromosomes during mitosis and meiosis.
Answer:
b. aggregate abnormally to form fibers and cannot adequately carry oxygen
Explanation:
The sickle cell hemoglobin is an abnormal form of hemoglobin. As the sickle cell hemoglobin release oxygen to the interstitial fluid, it forms long, stiff, and rod-like fibers. These aggregates of hemoglobin tend to bend the erythrocyte into a sickle shape. The sickled erythrocytes rupture easily and do not move easily through blood vessels. Sickled cells tend to stick together and form clumps which in turn cause blockages in blood vessels. Therefore, the presence of sickle cell hemoglobin adversely affects the ability of RBCs to carry oxygen.
Crater lake was produced when a stratovolcano collapsed, creating the crater.
This is false.
These are called perennial plants. Annual plants go through their entire life process within a single year and stop existing, meaning they can't produce fruit every year.
Embryonic tissue supporting filling and photosynthetic
Ground tissues conducting
Vascular tissues and covering
Dermal tissue
