Explanation:
On a peripheral blood smear, normal RBCs are disc-shaped with a pale-staining central area called the central pallor. When judging red cell size on a blood smear, the classic rule of thumb is to compare them to the nucleus of a small normal lymphocyte. The normal lymphocyte nucleus has an approximate diameter of 8 µm.
Answer: double helix
Explanation: The double helix of DNA is, like its name implies, in the shape of a helix which is essentially a three dimensional spiral. The double comes from the fact that the helix is made of two long strands of DNA that are intertwined—sort of like a twisted ladder.
The incident would be a volcanic eruption
Answer:
Most macromolecules are made from single subunits, or building blocks, called monomers. The monomers combine with each other using covalent bonds to form larger molecules known as polymers. In doing so, monomers release water molecules as byproducts.
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.
