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answer all of them and you have to be sure about your answers The cell membrane

ID: 92620 • Letter: A

Question

answer all of them and you have to be sure about your answers

The cell membrane is the structure that permits the maintenance of a stable internal environment (i.e. homeostasis). Select the accurate statement(s) about membranes.( chose all the correct)

A-membranes are mosaics of primarily phospholipids and proteins

b- to be fully functional, the membrane must be fluid at the optimal temperature for growth

c-molecules that can freely cross bilipid layers (membranes) are small and charged

d-membranes provide the rigid support for the cell, protecting it in harsh environments

2-Helical and icosahedral are terms used to describe the shapes of a virus( chose all the correct)

spike

capsomere

envelope

Capsid

core

3-Which of the following characteristics would be more frequently found among the Archaea than the Bacteria?( chose all the correct)

growth at high temperatures (greater than 80?C)

They can grow in very salty environments

They grow only in pH neutral environments

they are very common human pathogens

4-Which of the following is a 1:10 dilution?

1 ml into 10

1 ml into 9

1 ml into 99

1 ml into 44

5-

Which of the following is/are limiting factor(s) for the growth of microorganisms?

Optimal temperature

Limited space

Too many waste products

Not enough nutrients

Chloroplast membrane

A-membranes are mosaics of primarily phospholipids and proteins

b- to be fully functional, the membrane must be fluid at the optimal temperature for growth

c-molecules that can freely cross bilipid layers (membranes) are small and charged

d-membranes provide the rigid support for the cell, protecting it in harsh environments

2-Helical and icosahedral are terms used to describe the shapes of a virus( chose all the correct)

spike

capsomere

envelope

Capsid

core

3-Which of the following characteristics would be more frequently found among the Archaea than the Bacteria?( chose all the correct)

growth at high temperatures (greater than 80?C)

They can grow in very salty environments

They grow only in pH neutral environments

they are very common human pathogens

4-Which of the following is a 1:10 dilution?

1 ml into 10

1 ml into 9

1 ml into 99

1 ml into 44

5-

Which of the following is/are limiting factor(s) for the growth of microorganisms?

Optimal temperature

Limited space

Too many waste products

Not enough nutrients

Chloroplast membrane

Explanation / Answer

Fluid mosaic model describes the membrane structure as the mosaic arrangement of proteins embedded throughout the lipid bilayer as well as the fluid movement of the lipids and proteins alike.

Note- Lipid bilayer is impermeable for charged ions or polar molecules, lipid bilayers are not rigid only forms the external boundaries of the cell and are flexible responsible for homeostasis and are always fluid structure at body temperature.

Capsid is a symmetric protein shell which encloses the nucleic acid (genome).

Archaea live in habitat that are highly saline (extremely halophilic). Archaea can grow in very salty condition.

1ml into 9ml.

1:10 dilution means 1 part +9 parts of water (or another diluent).

Limiting factors for bacterial growth is-

All these factors are limiting factors for bacterial growth.