Answer:
<em><u>The water in lakes comes from rain, snow, melting ice, streams, and groundwater seepage. If water leaves a lake by a river or other outlet, it is said to be open. All freshwater lakes are open. If water only leaves a lake by evaporation, the lake is closed.</u></em>
Amoeba acquires it food by endocytosis, that is, a small region in the plasma membrane which ultimately forms a intra-cellular membrane-bound vescicle. It engulfs it food using its pseudopodia (temporary protrusion of the surface of the amoeboid cell used for feeding and movement) and forms a vacuole around it. When the food is already trapped inside, it releases a digestive enzyme to digest it. Intake of liquid particles is pinocytosis (cell drinking) while intake of solid particles is phagocytosis (cell eating).
Im 98% sure its the 3rd one... the other 2% im not that sure
1. These four factors can effect ways evolution occur:
<span>1.) Mutation
2.) selection
3.) Gene Flow
4.) Genetic Drift
2. </span>In biology, a mutation is the permanent alteration of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA or other genetic elements.
Selection, in biology, the preferential survival and reproduction or preferential elimination of individuals with certain genotypes by means of natural or artificial controlling factors.
In population genetics, gene flow is the transfer of alleles or genes from one population to another.
<span>Genetic drift is the change in the frequency of a gene variant in a population due to random sampling of organisms. </span>
Answer:
Option (A)
Explanation:
The Precambrian represents the time period, right from the beginning of the earth to about 540 million years back. It is divided into 3 parts, namely the Hadean, the Archean and the Proterozoic. Throughout this geological time, vast changes have taken place on earth. The first life forms of about 3.8 billion years old, that existed on earth were the simple unicellular organisms, whose traces were only found at some particular places. These organisms were very small and are comprised of soft bodies, so they were affected by the earth's dynamic processes. The organisms in order to get fossilized must contain hard parts. Due to the presence of soft bodies, the organisms were not fossilized and so it took a long time to demarcate that the late Precambrian organisms were animal-like life.
hence, the correct answer is option (A).
