Answer:
1.capsule
2.membrane composed mostly of lipopolysaccharide
3.membrane composed mostly of phospholipids
4.peptidoglycan
Explanation:
The cell wall of gram-negative bacteria is located outside the cell membrane and is composed of a single layer of peptidoglycan, followed by a second membrane composed of phospholipids (often called outer membrane) and finally a lipopolysaccharide layer, these three elements constitute the gram-negative envelope. Also, some bacteria produce a viscous secretion that spreads in the surrounding environment, forming a slime layer known as a capsule.
Answer:
a prezygotic barrier
Explanation:
Both wild tigers and lions are said to be reproductively isolated.
Reproductive isolation is defined as the existence of barrier between organisms of different species such that they cannot reproduce.
The mechanisms of reproductive isolation varies. While some act to prevent the formation of zygotes (in case of mating) between organisms of different species, some ensures that the resulting zygotes are invalid.
Reproductive isolation mechanisms that act to prevent fertilization and formation of zygotes are referred to as prezygotic mechanisms while those that ensure that invalid zygotes result (in case of successful fertilization) are referred to post zygotic mechanisms.
<em>The natural differences in the ranges of wild tigers and lions ensure that both animals do not mate with each other, let alone results in zygote. This is a form of pre-zygotic reproductive isolation mechanism.</em>
Break down food into simpiler compounds in order to supply nutrients to the body - monosacchrides, nucleotides, peptides, lipids.
Answer:
Muscle tissue and neural tissue
Explanation:
Excitability refers to the ability of muscle and nerve cells of the respective tissues to respond to a stimulus and generate an action potential. Both muscle cells and neurons respond to a stimulus and convert it into the action potential.
Action potential refers to the electrical signal. Propagation of action potential along the membranes of these cells results in muscle contraction and functioning of neurons.
The membrane potential of these cells changes in response to the stimulus and the changed potential is propagated to the other cells.