Some substances can cross a cell membrane against a concentration gradient, with the help of transport proteins. Such movement from LOW to HIGH concentration is called
a. active transport
b. simple diffusion
c. facilitated diffusion
d. exocytosis
e. plasmolysis

The phylogenetic tree illustrates the relationship between humans and our closest living relatives. the tree was based on biochemical comparisons, including dna and amino acid sequences. according to the biomolecular data, we could infer that a) the four organisms do not have a common ancestor. b) humans are more closely related to chimps than any other apes. c) chimps are more closely related to gorillas than they are to humans. eliminate d) there is no evidence if any relationship between the four branches on the tree.

Below, the levels of organization in a multicellular organism are shown from least to most complex. which level of organization can be described as several different types of tissues working together to perform a common task?

Select all that apply. why are common names not a good reference to a species? common names can be in different languages common names vary with location common names vary with culture common names vary with species color