Answer:
Sickle cell disease is due to a type of substitution mutation.
Explanation:
Sickle cell disease is a condition that is transmitted from parents to children in an autosomal recessive inheritance pattern. It is due to a mutation that is capable of altering the shape of the erythrocyte, as well as its ability to circulate and carry oxygen.
The mutation that occurs in sickle cell disease is due to an alteration in the β-chain of hemoglobin, caused by the substitution of thymine base by adenine in the DNA that determines it. As a result, valine replaces glutamic acid in the β-chain amino acid sequence, with the consequences described.
- <em>The other options are not correct because </em><u><em>deletion, duplication and translocation </em></u><em>correspond to chromosomal mutations, not responsible for sickle cell disease.</em>
Answer:
A tissue.
Explanation:
If a group of cells have the same function, they can be called a tissue because they all work together to kind of form a "super cell" as I like to call it.
Hope this helped!
~Mschmindy
Answer:
- A Tongue-shaped structure called radula for grasping food --> Mollusca
- Fleshy lobe-like structure called parapodia --> Annelida
- Spongin fibers or spicules for support ---> Porifera
Explanation:
Radula: This is an organ used in feeding by mollusks. It constitutes a highly developed feeding organ. The radula has is conformed of small teeth-like structures located in rows. Lateral teeth vary in shape and size. The movements of the radula during feeding are complexes acting as a scratcher on the surface to get the food.
Parapodia: These are characteristic lateral appendixes that emerge and extend from each of the body segments of invertebrates such as polychaetes. The typical parapodium is a fleshy prolongation more or less laterally comprised and is composed of a superior branch (notopodium) and an inferior branch (parapodium).
Spicules: Sponges (Poriferous) skeleton is composed of calcium carbonate and siliceous micro-structures called spicules. Their morphology is so varied that it is used in taxonomy for identification and classification.
There are different kinds of spicules:
- Monoaxonic spicule: needle-shaped, straights or curves
- Tetraxonic spicules: they have four prolongations
- Triaxonic or Hexaxonic spicules
- Poliaxonic spicules
Two terms can be applied to any of these spicules kinds:
- Megaspicules: They are elongated and compose the main architecture of the sponge skeleton
- Microspicules: Variable in shape and size, with ancillary functions
Sponges have few predators because of the spicule structures and their high toxicity. Many of them are capable of perforating soft tissues and producing urticant substances.
Answer:
It is well supported by evidence.
