The answer is that they are somatic cells
Answer:
Epidermal cells secrete the waxy hydrophobic substance cutin that polymerizes on the surface, forming a barrier to water evaporation. Epidermal cells are transparent because their plastids remain small and undifferentiated; hence light readily penetrates through to the photosynthetic tissues beneath the epidermis.
Explanation:
prevents backflow into the left atrium
Answer:
When scientists studied patterns in the rocks of the ocean floor, they found more ... Making Models What characteristic of the ocean floor did you observe as you swept ... recorded the magnetic memory of rocks on both sides of a mid-ocean ridge. ... The Glomar Challenger, a drilling ship built in 1968, gathered the samples.
Explanation:
Glomar Challenger: Drillship of the Deep Sea Drilling Project. It was on June 24, 1966, that the Prime Contract between the ... One of the most important discoveries was made during Leg 3. ... After analysis of samples, scientists concluded that the ocean floor is probably no older than 200 million years.
Answer:
Jaws and a swimming bladder
Explanation:
A defining characteristic between sharks and rays that distinguish them from ray-finned fish is the *possession of jaws in sharks* and rays;and the *possession of swimming bladder in ray-finned fishes*.
Characteristics of sharks and rays are as follows :
They are cartiiliginous fishes; they possess *strong jaws* lined with teeth; body dorsoventrally flattened, fusiform (spindle shaped) with heterocercal tail(diphycercal in Chimaeras); paired fins; *no swimming bladder or lungs*; pelvic fins in males often modified to form clappers; Gill arches internal to gills; reduced notchord; lateral-line system; paired nostrils; internal nares absent; separate sexes; internal fertilization and direct development; oviparous, oviparous, or ovoviviparous. Examples include, Spiny dog fish or dog shark, Ray Raja, Chimaera.
Characteristics of ray-finned fishses:
They generally lack paired fins; no internal nares; *air sacks usually function as swimming bladder*; skeleton usually well ossified. Blind olfactory sacs (do not open into the mouth); Tail homocercal. Examples include Tilapia, Claris,and Polypterus.
