Intro to Cell Homeostasis

The structures inside the cells, called organelles, have different functions to sustain the life of an organism. What are the jobs of the organelles inside our cells to support our life function? Select all that applies.

• producing molecules such as proteins

• production of energy

• generating large amount of heat

• storing genetic information

• digesting large particles of foods

What is homeostasis?

• organism's ability to respond to the changing environment

• organism's ability to maintain a stable internal environment even with external condition change

• when a cell maintains a stable internal environment such as temperature, pH, etc.

• when a cell break downs and remove wastes

Maintaining internal balance, homeostasis, is an essential healthy condition. What needs to be maintained in the human body system? Check all that applies.

• glucose level in the blood stream

• body temperature

• daily cardio exercise and calories intake

• at least 3 meals a day

What organelle or part of the cell plays an important role in cell homeostasis?

• nucleus

• ribosomes

• vacuole

• plasma membrane

All cells, prokaryotic bacteria and all eukaryotic cells such as plants and animal cells are surrounded by a plasma membrane. True or False

• True

• False

• Sometimes

• I am not sure.

Cell or plasma membrane act as a barrier between inside and outside of the cell. It is selectively permeable or semi-permeable. Which correctly describe semi-permeable plasma membrane?

• It allows all foods and nutrients to enter the cell.

• It allows some molecules to go inside the cell but not all.

• It does not allow any nutrients to go inside the cell.

• It does not allow water and glucose to go inside the cell

Label the plasma membrane, using the letters/numbers as a guide to place your labels.

a

b

c

Hydrophobic Tail

Hydrophilic Head

Phospholipid Bilayer

Plasma or cell membrane is primarily made of

• cholesterol molecules

• proteins molecules

• lipids molecules

• phospholipid molecules

Look at the picture on the left, which correctly describe the plasma membrane?

• a lipid bilayer

• a protein bilayer

• a phospholipid bilayer

• a phospholipid single layer

Matching

• attract water

• hydrophilic

• repel water

• hydrophobic tails are made of

• lipids

• hydrophilic heads are made of

• phosphorus

• hydrophobic