Cell Biology

Question 1

List the functions of water, carbs and lipids

Answer 1

Water - Blood volume, temp, blood pressure. lubrication, transport

Carbs - Energy, Nervous system

Lipids - Absorption of vitamins, cell membranes, Insulation

Question 2

What is the difference between glycogen and glucose in terms of location and general
structure and function?

Answer 2

Glucose is a monosaccharide while glycogen is a polysaccharide ( many units)

Blood Vs Muscles/Liver

Question 3

What are the names of the processes by which polysaccharides are formed and
broken down? In which of these is water used, or formed?

Answer 3

Hydrolysis - Water Used

Question 4

What are the main types of lipid found in the body?

Answer 4

Triglycerides. Triglycerides are lipids you obtain from food sources of fat, such as cooking oils, butter and animal fat. …
Steroids. Steroids are a type of lipid that includes hormones and cholesterol. …
Phospholipids.

Question 5

What are the products of triglyceride breakdown?

Answer 5

free fatty acids and glycerol. Fatty acids can then be taken up by cells via the fatty acid transporter (FAT).

Question 6

. State the functions of proteins

Answer 6

Repair, Muscle building, DNA

Question 7

Describe the basic structure of proteins.

Answer 7

The primary structure of a protein refers to the linear sequence of amino acids in the polypeptide chain. The primary structure is held together by covalent bonds such as peptide bonds, which are made during the process of protein biosynthesis.

Question 8

What is meant by secondary, tertiary and quaternary protein structure?

Answer 8

Secondary - aminos linked by hydrogen bonds
Teriary - 3D SHAPE The protein molecule will bend and twist in such a way as to achieve maximum stability or lowest energy state. fashioned by many stabilizing forces due to bonding interactions between the side-chain groups of the amino acids.
Quartenart - Formation of protein subunits

Question 9

. What is denaturation of proteins and what are the causes?

Answer 9

Disruption/destruction of secondary/ tertiary to Primary

Heat

Question 10

What are conjugated proteins?

Answer 10

A conjugated protein is a protein that functions in interaction with other (non-polypeptide) chemical groups attached by covalent bonding or weak interactions. ie., lipoprotein

Question 11

Define the term ‘enzyme’.

Answer 11

Enzymes are macromolecular biological catalysts

Question 12

How do enzymes co-operate?

Answer 12

By folding to allow smaller molecules to fit

Question 13

. Describe how enzymes work, i.e. ‘induced fit’.

Answer 13

the binding of a substrate or some other molecule to an enzyme causes a change in the shape of the enzyme so as to enhance or inhibit its activity.

Question 14

What factors can affect enzyme activity? In each case explain the reason why

Answer 14

Temp (more random collisons, pH, Substrate concentration, bonding ETC

Question 15

Describe the difference between the following co-factors:
Activators (give examples)
Prosthetic groups (give examples)
Co-enzymes (give examples)

Answer 15

activators are molecules that bind to enzymes and increase their activity. They are the opposite of enzyme inhibitors.

Prosthetic groups are cofactors that bind tightly to proteins or enzymes. A

Co Enzymes - molecules that increase the rate of reaction or are required for enzyme function

Question 16

What are:
Reversible inhibitors (give examples)
Irreversible inhibitors (give examples)

Answer 16

Non reversible - Chemical change

Reversible - Non-covalent bond

Question 17

Define:
Homeostasis;
Negative feedback;
Dynamic equilibrium;
'Open system

Answer 17

Negative feedback causes a decrease in function. Often it causes the output of a system to be lessened; so, the feedback tends to stabilize the system.

Dynamic Eq. - balancing when a cell requires energy to maintain

an Open system is one in which materials and energy are transferred between organisms and the exterior environment. In an open system, there is some type of boundary that allows energy or materials to cross over for the purpose of growth and change.

Question 18

What is the difference between positive feedback and negative feedback? Give an
example of each.

Answer 18

A positive feedback loop causes a self-amplifying cycle where a physiological change leads to even greater change in the same direction. A negative feedback loop is a process in which the body senses a change, and activates mechanisms to reverse that change.

Question 19

What is the structural arrangement of phospholipid in a cell membrane?

Answer 19

Middle hates water!

Question 20

What other lipids are present in a cell membrane and what are their functions?

Answer 20

classes of membrane lipids are phospholipids, glycolipids, and cholesterol.

Glyco Their role is to maintain stability of the membrane and to facilitate cellular recognition.

Cholesterol essential to maintain both membrane structural integrity and fluidity

Phospho - form BI layer

Question 21

What are the functions of membrane proteins?

Answer 21

Interaction, signalling, Transport

Question 22

. What are the functions and properties of the plasma membrane?

Answer 22

Protection/movement of substances

Question 23

Give an example of:

a. a cell that does not contain a nucleus,
b. a cell that is multinucleate.

Answer 23

Prokaryotes (meaning ‘before nucleus’) are cells without a definite nucleus.DNA floats in the cytoplasm and they divide through mitosis E.COLI

Multinucleate cells (also called multinucleated or polynuclear cells) are eukaryotic cells that have more than one nucleus per cell, i.e., multiple nuclei share one common cytoplasm. - MUSCLE

Question 24

What does the term ‘syncytium’ mean?

Answer 24

a single cell or cytoplasmic mass containing several nuclei, formed by fusion of cells or by division of nuclei.

Question 25

What are Cilia?

Answer 25

is an organelle found in eukaryotic cells. Helps movement of cell or substance

Question 26

State the structure and function of the following:
Lysosomes
 Golgi apparatus
Ribosomes
 Endoplasmic reticulum

Answer 26

Lysosome Contains digestive enzymes to help break food down
Golgi Apparatus Make, process and package proteins
Ribosomes Make protein
Endoplasmic Reticulum Called the “intracellular highway” because it is for transporting all sorts of items around the cell.

Question 27

What is the difference between cilia, microvilli and villi?

Answer 27

Cilia are found on ciliated epithelial cells, like in the lungs. They wave rhythmically to move dirt and mucus out. Microvilli are found in the small intestine, and increase the surface area for nutrient absorption

Question 28

Give three examples of cell inclusions and their functions.

Answer 28

Inclusions are stored nutrients, secretory products, and pigment granules. Examples of inclusions are glycogen granules in the liver and muscle cells, lipid droplets in fat cells, pigment granules in certain cells of skin and hair, water-containing vacuoles, and crystals of various types.

Question 29

Explain, with examples, the following terms:
Passive processes
 Simple Diffusion
 Facilitated Diffusion
Osmosis
Active processes
Active transport 
Bulk transport

Answer 29

Passive - No energy
Simple Diff. - Without aid of protein
Facilitated diffusion -spontaneous passive transport of across a cell’s membrane via specific transmembrane integral proteins
Osmosis- Low to high
Active - lower to higher. requires energy
Active transport - Against concentration gradient
Bulk - Movmeent of macromolecules exocytosis and endocytosis, and both require the expenditure of energy (ATP

Question 30

What is the difference between endocytosis and exocytosis?

Answer 30

n endocytosis, the body cells ingest various molecules such as proteins, polar molecules, and other substances, through their hydrophobic plasma membrane. … Exocytosis is the release of some chemical from a cell

Question 31

What is the difference between pinocytosis and phagocytosis?

Answer 31

Phagocytosis is the process by which living cells called phagocytes envelop or engulf other cells or particles, whereas pinocytosis is a process in which liquid droplets are ingested by living cell

Question 32

Under aerobic conditions, what are the products of glycogen catabolism?

Answer 32

glucose-1-phosphate

Question 33

Where does aerobic respiration occur within a cell?

Answer 33

in the MITOCHONDRIAL MATRIX or on the inside of the inner membrane of mitochondria (

Question 34

What happens to lactic acid?

Answer 34

The Cori cycle - moves to liver and converted to glucose

Question 35

What types of cell death are there?

Answer 35

Apoptosis or Type I cell-death, Disease/ cancer

autophagy or Type II cell-death - naturall/ starvation

necrosis is a non-physiological process that occurs as a result of infection or injury. Necrosis is cell death caused by external factors such as trauma or infection,