cell structure and transport

Question 1

Draw and label a diagram of an animal cell that includes a nucleus, ribosomes, a golgi body, rough and smooth endoplasmic reticulum and mitochondria.

Question 2

describe the functions of vacuoles

Answer 2

Vacuoles store waste materilas or products that are produced

Question 3

3. Describe the function of the smooth endoplasmic reticulum.

Answer 3

Smooth ER responsible for synthesis of lipids and production and secretion of steroid hormones.
- The rough ER, studded with millions of membrane bound ribosomes, is involved with the production, folding, quality control and despatch of some proteins.

Question 4

What features of cells (organelles) are always found in both prokaryotes and eukaryotes?

Answer 4

Features that are found in both prokaryotic and eukaryotic cells are ribosomes, nuclieic acid, cytoplasm, type of cell membrane

Question 5

5. Explain the importance of having compartments (membrane bound organelles) in Eukaryotic cells.

Answer 5

This allows organelles within the cells to control what enters and leaves it by using a selectively permeable membrane. this allows reactions to occur at a more efficient rate

Question 6

outline why prokaryotic cells have limited function

Answer 6

because they do not contain membrane bound organelles meaning its cellular processes arent as efficient as eukaryotic cells

Question 7

7. What are the four classes of biological molecules?

Answer 7

The 4 classes of biological molecules are lipids, nucleic acid, carbohydrates, proteins

Question 8

8. Discuss the structure of carbohydrates in terms of chemical composition and varying size.

Answer 8

Carbohydrates are made up of 1C 2H 1O  
simple sugar=  monosaccharide 
2 sugars connected= disaccharide 
Multiple sugars= polysaccharides
They're the body's primary source of energy and the brain's preferred energy source, carbs are broken down in the body by glucose which is a sugar.

Question 9

Discuss the four key roles of lipids in cell structure/function.

Answer 9

lipids are energy stores, transport of substances in and out of the cells, protection of cells, a structural components of cell membrane

PEST

Question 10

10. Of the 20 amino acids found in human cells, 9 are considered “essential amino acids”. Explain what is meant by this statement.

Answer 10

9 amino acids are essential because they cannot be synthesised by cells in your body. The rest of the amino acid are synthesised (It is the process of combining two or more components to produce an entity.)

Question 11

11. Why are proteins folded? What happens when they’re misfolded?

Answer 11

Proteins are folded to make them more useful and to function correctly . Alzheimers, parkinsons are caused by misfolded proteins larger.

Question 12

12. Describe why it is important for lipids to be long chains.

Answer 12

Its important for lipids to be in long chains as it makes them non polar which means that theyre water resistant not allowing water in.

Question 13

Draw a diagram of a mitochondria and label the following:
matrix, cristae, outer membrane, inner membranem intermembrane.

also explain how the structure is specialised for mass production of atp

Answer 13

Matrix- a nutrient rish fuild that provides all the resources and reactants needed for the production of ATP
Cristae- rich with enzymes known as atp synthases
Outer membrane-
inner membrane- has inner folds called the cristae
the cristae structure allows for a larger surface area meaning more reactions can take place, these cristae are also rich with enzymes known as ATP synthases

Question 14

14. State 3 independent different forms of evidence for the endosymbiotic theory and explain how they support the theory.

Answer 14

• both have 2 cell membranes
  
  • contain their own DNA and ribosomes
  • replicate through binary fission

Question 15

what is the endosymbiotic theory?

Answer 15

this theory proposes that mitiochondria were once a small bacterial cell that were consumed by a larger prokaryotic cell and rather than breaking down the 2 formed a symbiotic relationship

Question 16

Discuss the structure of the phospholipid bilayer shown on the left. Include in your discussion the importance of the.

Answer 16

This structure is made up of 2 different lipids, each containing hydrophilic phosphate head and hydrophobic tails. Phospholipids pair up and the hydrophobic tails pair up so their tails are facing eachother both repelled from water

Question 17

Describe the role of adhesion proteins in the cell membrane.

Answer 17

Used to join cells together to form tissue

• enables interactions and communication from other cells
• allows to maintain shape

Question 18

Recognition proteins (glycoproteins) are important signaling molecules. Describe the role of these proteins in blood transfusions and why it is so important to only receive blood from those with the same type blood as you.

Answer 18

These act as a flag which allows immune cells to differentiate between host cells and foreign cells. Once the wrong type of blood has been infused the recognition proteins will pick it up and trigger the patients immune system to attack the transfused blood.

Question 19

Explain the term “concentration gradient”

Answer 19

concentration gradient is the difference in concentration from one area to another. if one side has high concentration and the other side has low then there is a high doncentration gradient.

Question 20

Outline the difference between passive and active transport.

Answer 20

Passive transport does not require energy and include processes like simple diffusion and facilitated diffusion as well as osmosis
Active transport dose require energy and are processes like endocytosis and exocytosis, which are forms of bulk transport

Question 21

what sthe difference between carrier proteins and channel proteins?

Answer 21

Channel – narrow passage way, allows ions to pass through, when no gradient exist the channels have the ability to close

Carrier – bind and change shape of molecule ans release to other side, depend on the concentration gradient.

Question 22

draw diagram of a carrier protein and a channel protein

Question 23

Define the terms hypertonic, hypotonic and isotonic

Answer 23

Hypertonic- the solution has a high concentration in the (solute) than the cell (tiny cell)

Hypotonic- the solution has a low concentration in the (solute) than the cell (large cell)

Isotonic- solution has the same solute concentration than the cell( unchanged size of the cell)

Question 24

Describe why it is important for red blood cells to be stored in an isotonic solution.

Answer 24

If a cell is placed in an isotonic solution, there will be no net flow of water into or out of the cell, and the cells volume will remain stable.

Question 25

what are the 2 types of bulk transport? and what do they do?

Answer 25

endocytosis- transport into the cell
2 different types
phagocytosis– engulfs solids into cell
pinocytosis- engulfing liquids

exocytosis transports out of the cell

Question 26

when is active transport used?

Answer 26

• when the cell needs to work against the concentration gradient
• for example digestive enzymes

Question 27

. Outline two bodily processes that depend on exocytosis any why they need to use this method of transport.

Answer 27

• Hormones produced in the cells are released into the blood stream by exocytosis like digestive enzymes.
• Nerve cells also use exocytosis to communicate.

Question 28

Explain why substances that can undergo simple diffusion will typically enter a cell faster than those which rely on facilitated transport.

Answer 28

Because facilitated diffusion has to go through transmport proteins as well as the the phosphide bilayer and simple diffusion allows particles to only pass through the plasma membrane.

Question 29

. Assuming a cell is trying to acquire a certain type of nutrient through simple diffusion, describe and explain the effect on the rate of transport if: temp increased, concentration outside the cell increased, the concentration inside the cell, the surface are increases

Answer 29

The temperature is increased: the rate of diffusion will increase because there is increased movement meaning there is more contact between the cells
The concentration outside the cell is increased: then the rate of diffusion will increase as the solute is trying to enter the cell
The concentration inside the cell is increased: then the rate of diffusion is decreased ???
The surface area increases: the rate of diffusion is increased as the object has more access points that the particles could enter the object in.

Question 30

draw a complete diagram of the cell membrane including proteins, cholestrol and the phospholipid bilayer.

Question 31

whats the name given to the model of the cell membrane

Answer 31

the fluid mosaic model

Question 32

what is osmosis

Answer 32

osmosis is specific to the diffusion of water molecules, that is the diffusion of the solvent rather than the solute

Question 33

what is feild of view? how dp you figure out the total magnification ?

Answer 33

is the maximum area visible when looking through the microscope eyepiece
total magnification= ocular magnification (10) x objective magnification ( can be 40,4,10)

Question 34

list the features of a eukaryotic cell

Answer 34

• much more complex
• can be single or multicellular
• contains membrane bound organelles ( mitochondria, lysosomes)
• DNA contained in nucleus
• varying numbers of chromosomes

Question 35

list the features of a prokaryotic cell

Answer 35

• very simple and singleed celled
• doesnt contain membrane bound organelles
• no nucleus
• DNA exists as a single cellular chromosome

Question 36

what are the similarities of prokaryotic and sukaryotic cells

Answer 36

• same type of cell membrane
• both have genetic material in the form of nucleic acid
• both have cytoplasm
• both have ribosomes to make proteins

Question 37

draw a eukaryotic cell

Question 38

draw a prokaryotic cell

Question 39

what do proteins do? and what are the different lengths of amino acids called?

Answer 39

they contribute to structure and function, an enzyme is a special protein that speeds up biochemical processes.

peptides- short chain of amino acids
polypeptides- multiple peptides
chain of polypeptides- proteins

Question 40

what makes something a biomacromolecule

Answer 40

a large molecule that is used by living organisms in either structural or functional biochemical processes.

Question 41

how do enzymes work?

Answer 41

the enzyme will bind the substrate at the active site, the enzyme and substrate will chemically bind together and form the enzyme-substrate complex.

Question 42

what happens when a protein denatures

Answer 42

it unfolds

Question 43

factors effecting denaturing? what happens to a protein once its denatures?

Answer 43

temp, ph as different cells have differnt optimum conditions

once a protein has denatured its no longer in the requires conformation and it will no longer be able to bind the substrate loosing its ability to catalyse reactions.

Question 44

whats an inhibitor

Answer 44

molecules effecting the binding of other molecules, they are either competitive or non-competitive

competitive- will bind at the active site to stop the substrate from binding

non-competitve- will bind somewhere else on the enzyme forceing the active site to change shape so the substrate cannot bind with the active site

Question 44

whats an inhibitor

Answer 44

molecules effecting the binding of other molecules, they are either competitive or non-competitive

competitive- will bind at the active site to stop the substrate from binding

non-competitve- will bind somewhere else on the enzyme forceing the active site to change shape so the substrate cannot bind with the active site

Question 45

whats an activator

Answer 45

when activators bind together the enzyme is activated

cofactors- are small inorganic substances often metal ions
coenzymes- are organic substances such as vitamins

Question 46

whats an anabolic enzyme

Answer 46

anabolic enzymes join molecules to create larger molecules and store energy an example of this is DNA ligase

Question 47

whats a catabolic enzyme

Answer 47

breaksdown molecules into smaller component parts for example amylase