7.0 + 7.1

Question 1

Modern Cell Theory

Answer 1

1.The cell is the fundamental unit of structure and function in living things.

2. All organisms are made up of one or more cells.
3. cells arise from other cells through cellular division.

Question 2

Expanded Modern Cell Theory

Answer 2

1. Cells carry genetic material passed to daughter cells during cellular division.
2. All cells are essentially the same in chemical composition.

3.Energy flow occurs within cells (biochemistry)

Question 3

Hydrophobic

Answer 3

Substances unattracted to water.

Question 4

Hydrophilic

Answer 4

Substances attracted to water.

Question 5

Amphipathic

Answer 5

Molecules made of hydrophilic and hydrophobic substances.

Question 6

Are Phospholipids hydrophobic, amphipathic or hydrophilic?

Answer 6

Phospholipids are amphipathic because the phosphilid is hydrophilic and the hydrocarbon chains or tails are hydrophobic.

Question 7

How do Phospholipids form Bilayers?

Answer 7

The tails are attracted to eachother and repelled from water. they form a wall up against eachother with the heads facing the water that the phospholid head is attracted to.

Question 8

Cell Membrane primary function

Answer 8

Form a barrier through which ions and hydrophilic molecules cannot easily pass. This is created by the phospholipid bilayer.

Question 9

Membrane protein functions (JETRAT)

Answer 9

Junctions- connect and join two cells together

Enzymes- Fixed to membranes, localizes metabolic pathways

Transport-responsible for facilitated diffusion and active transport

Recognition- may function as markers for cellular identification

Anchorage- Attachment points for cytoskeleton and extracellular matrix

Transduction- function as receptors for peptide hormones

Question 10

Integral proteins

Answer 10

Integral proteins are embedded in the hydro carbon chains in the membrane with the hydrophilic heads sticking through.

Question 11

Peripheral proteins

Answer 11

Proteins that are entirely hydrophilic and do not embed into the cell membrane.

Question 12

How do peripheral proteins attach?

Answer 12

Either by attaching temporarily to a integral protein or using a single hydrocarbon chain to anchor to the membrane.

Question 13

Channel proteins

Answer 13

Integral proteins lines with polar amino acids that substances such as water use to move through proteins instead of the oily membrane.

Question 14

ligands

Answer 14

Proteins that unlock certain channel proteins to control substance release. ie: Insulin unlocks the protein channels that transport glucose

Question 15

Why is cholesterol located between the layers in the cell membrane?

Answer 15

Most of cholesterol is hydrophobic and attracted to the tails in the membrane except one hydroxyl (OH) group. This group is attracted to the heads and the cholesterol molecule is positioned between the layers.

Question 16

Role of Cholesterol in the Cell Membrane

Answer 16

Cholesterol stops too many tails from attaching to each other and solidifying and restricts motion and fluidity of the membrane

Question 17

Function of integral proteins

Answer 17

Substances such as water take advantage of the structured tunnels to move through proteins. (Channel proteins)

Question 18

What are Oligosaccharide Attachments

Answer 18

Short carbohydrate chains attached to phospholipids (glycolipids) or proteins(glycoproteins).

Question 19

Function of Oligosaccharide Attachments

Answer 19

Function as markers for interaction and identification of cell types. ie: blood types