B. DNA is heated to separate strands
<span>First.PCR reaction</span>
Cell membrane i think as I remember
D. A variable or alteration to one part that affects an entire system
Explanation:
When talking about natural and physical systems, change is a variable or alteration to one part that affects an entire system.
Systems are groups of processes that have the same overall function. There are several types of interacting components that makes up both physical and natural systems in our world.
- The part of system is related and interconnected via the changes they undergo.
- Changes typically causes variation or alteration of parts of a system.
learn more:
Biogeochemical cycle brainly.com/question/3509510
#learnwithBrainly
Alfred Marshal was one of the most influential economists of his time and the author of the Principles of Economics book which was the principal economic textbook in England for long years. During his economic theory development, he borrowed a concept from the marginalists which is the theory of demand and the collective result of buyers who yearns services and products or the concept of scarcity.
<h2>Angiosperms </h2>
Explanation:
Angiosperms are the most diverse group of plants, some statements which reflect angiosperm adaptations to life on land:
- Flowers attract animal pollinators carrying pollen from other plants of the same species
- Fruits aid in the dispersal of seeds by wind or by animals that carry or eat the fruits
- In many angiosperms, the male gametophyte contained in a pollen grain can be transported many miles away by wind or animal pollinators
- Floral parts of the sporophyte protect the reduced female gametophyte from drying out and from UV radiation
- Seeds protect and nourish plant embryos, and fruits protect the seeds
- Seeds enable plant embryos to be dispersed long distances from the parent plant via wind or animals
