It has to be a , T cells are are your killer cells
Answer: The correct answer to the question is option D
CAST FOSSILS.
Explanation: To understand what a cast fossil really is,let's look at what a fossil is generally.
Fossils are traces of what are formed and left of living things which dates back to a long time ago. Fossils are often found in sedimentary rocks examples; Shales, limestone and sandstone.Fossils are left over animals/plants.
Not all fossils are remains of living things.
There are different types of fossils; FROZEN FOSSILS; When an animal is trapped and freezed as a result of drop in temperature.
IMPRINT FOSSILS; They are prints made and left when animals walk or move over clays,these imprints dries and get covered by other sediments.plants also leave imprint fossils.
AMBER FOSSILS; These are fossils that are formed when tiny insects and bugs become trapped in saps of trees, when these saps dries up,they become hard and and an Amber is formed.(a seminiferous material).
CAST FOSSILS; These are fossils that form as a result of the death of plant,animal or any organism,when this happens,chemical reaction occurs which brings about a degradation in the bones and flesh if the organism,cavities are formed and minerals are deposited in those cavities bringing about a cast which looks like the original form or image of the organism.
Answer:
c
Explanation:
seas water isn't fresh water
Heterotrophic bacteria can't create their own food,but it can obtain energy from carbohydrates and other organic materials
