<span>Meiosis consists of one round of DNA replication accompanied by two rounds of cell division.
Before meiosis starts, the cell </span><span>goes through an interphase period in which it grows, replicates its chromosomes to have enough material to divide for the daughter cells.
Unlike mitosis, meiosis has 2 cell division (meiosis
I and II). At the end of the first division, </span><span>each cell has half the number of chromosomes of the parent cell. At the end of the second division</span> there is separation of the sister chromatids
It might be 23% because 77% of water covers earth and most of the water is either polluted or salt water.
The correct answers are:
Tissue level- similar cells work together to accomplish a goal.
Examples of tissue are muscles, skin, bone, and brain (nervous tissue).
A sponge is an example of an organism that is only organized to the cellular level.
Prokaryotic bacteria are surrounded by a cell membrane that contains the transport proteins to regulate the entry and exit of materials through the cell, the cell wall to help maintain cell shape and structure, and the capsule, which aids against drying out and protects bacteria from a host's immune system.
<h3><u>Explanation:</u></h3>
Bacteria are the prokaryotic organisms that are found in every part of Earth. These organisms do have an interesting ultrastructure. The coverings of the bacteria are three in layer. They are
A. The outer capsule.
B. The middle cell wall.
C. The inner cell membrane.
The capsule is the outermost covering of bacteria that is formed of different slimy materials. These materials contains hygroscopic substances which can absorb water from the surroundings even when the water concentration in outside is very very low. This layer of protection outside bacteria help them to protect themselves against drying out at dry conditions.
The middle cell wall is formed of polymers of N acetyl glucosamine and N acetyl muramic acid. This layer is chitin in nature and is strong enough to maintain the shape and size of bacteria irrespective of outer conditions.
The innermost layer of bacteria is cell membrane which is formed of proteins and lipids bilayer and this cell membrane contains different transport for proteins which help in transport of different substances like water and nutrients inside the cell by means of active transport or passive diffusion.
Answer:
b.Movement of phospholipids in the plasma membrane from one monolayer to the other requires the polar or charged head groupd to enter the hydrophobic interior of the lipid bilayer. This process requires a large positive change in free-energy, thus making this type of movement unlikely without an input of energy
The plasma membrane serves a protective function for the cell and is a selective membrane for particles entry
