The outer membrane contributes an extra barrier in gram-positive bacteria that makes them impervious to some antimicrobial chemicals, so they are generally more difficult to inhibit or kill than are gram-negative bacteria. A. TrueB. False

The statement is false

Explanation:

Gram-positive bacterial cell wall is made up of only the peptidoglycan layer and it does not have an extra barrier that protects it from some antimicrobial chemicals. Gram-negative bacteria have two layers of cell wall peptidoglycan layer and a lipopolysaccharide layer.

So as gram-negative bacteria have an extra layer of cell wall therefore it is less sensitive towards antimicrobial chemicals than gram-positive bacteria. So grams positive bacteria are an easy target for antimicrobials than gram-negative bacteria. Therefore the statement is false.

d concave shape of wave rock

explanation:

the concave shape of wave rock is a very good evidence that supports the evolution of earth due to chemical weathering. if we talk about structure of   wave rock, studies have estimated that it is around 2.7 billion years old. it also serves as the foundation of evidence that it was the place where australian continent began to form.

how the structure of wave rock was created?

studies suggest that structure of wave rock was created when the surrounded area was started to weather due to which deposition of material started on the part of land which now contains wave rock.

the structure of wave rock is considered to be one of the best-known landforms in australia. at the height of around 15 cm, there can be found flared slopes which formulate the margins of hyden rock. it is now assumed by geologists that wave rock was created by subsurface water-induced weathering and not by glaciers, waves or wind.

due to deposition of material over the period of long time, the wave rock became tougher and tougher due to weathering from surrounding terrain. this makes it a physical evidence that supports   the evolution of earth due to chemical weathering.

hope it !