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Question 0

Outer plasma membrane

Answer 0

Regulates what leaves and enters a cell

Question 1

Common properties of cells

Answer 1

Outer plasma membrane
DNA
Cytoplasm

Question 2

DNA

Answer 2

Copying and reading genetic instructions in a cell

Question 3

Cytoplasm

Answer 3

Fluid (cytosol) in cell that contains various components.
Cytosol is like water with dissolved nutrients, ions, soluble and insoluble proteins and waste products. It contains organelles which perform the function of the cell.

Question 4

Organelles

Answer 4

Plasma membrane
Nucleus
Endoplasmic reticulum
Mitochondria 
Cytoskeleton 
Golgi body 
Vesicles

Question 5

Plasma membrane

Answer 5

Cells regulate substances which enter and leave.

Even the relative charge of inside some types of cells versus outside those cells is regulated

Question 6

Extracellular fluid

Answer 6

Water with dissolved electrolytes (conduct electricity).
A cell membrane which is made of non-polar (fatty) substances will prevent extracellular fluid entering the cell, or intracellular fluid leaving the cell.
Contains sodium ion and chloride ion - positive charge

Question 7

Intracellular fluid

Answer 7

Contains proteins (negative) and a little potassium ion - negative charge.

Question 8

Lipid bilayer

Answer 8

Made up of Hydrophilic (water loving; polar) part and hydrophobic (non-polar) part.
Self-healing

Question 9

Glycoproteins

Answer 9

Span the width of the bilayer.
Protein + carbohydrate
Complicated structure

Question 10

Active transport

Answer 10

Proteins require energy to control entry and exit of ingredients to and from cells.

Question 11

Receptors

Answer 11

Proteins that don’t spam the width of the lipid bilayer.
Perform function on the outer or inner surface of the cell.
They receive molecules travelling around in the extracellular fluid.

Question 12

Nucleus

Answer 12

Usually just one in a cell, unless in skeletal muscle cells (which have many)
Mature red blood cells have NO NUCLEUS.
Has its own phospholipid bilayer with pores that allow particles of information (blueprint for creating molecules) to leave the nucleus. These particles are chromosomes.

Question 13

Endomembrane system

Answer 13

Endoplasmic reticulum is a network of membranes connected to nucleus that ‘snakes’ through the cytoplasm.

Question 14

Rough endoplasmic reticuli

Answer 14

Manufacture and store proteins for the plasma membrane and elsewhere.
Consists of molecules called ribosomes.

Question 15

Smooth endoplasmic reticuli

Answer 15

Help manufacture fatty acids, steroids and phospholipids.

No ribosomes.

Question 16

Golgi apparatus

Answer 16

Positioned between ER and cell’s surface.
Layers of hollow saccules.
Collect the protein/glycoproteins secretions formed in ER. Organise and package secretions into vesicles.

Question 17

Vesicles

Answer 17

Travel through the cell wall, fuse through it and release their contents (secretions) into the extracellular fluid.

Question 18

Lysosome

Answer 18

Created by Golgi apparatus
Release inside the cell in the cytosol
Fuse with damaged organelles.
Absorbs this material and takes it to the cell membrane for ejection.

Question 19

Exocytosis

Answer 19

Removal of waste through the cell membrane

Question 20

Mitochondria

Answer 20

Inside the cell and assist with creation of the energy molecule ATP.
Liver cells have many mitochondria (up to 20% of their volume).
Red blood cells have none.
Oxygen is required to make ATP, with Carbon dioxide and water produced as waste.

Question 21

ATP

Answer 21

Adenosine triphosphate
Molecule derived from a variety of different, larger dietary molecules (sugars, lipids and protein)
The P splits off the ATP molecule and energy is released for use in the rest of the body.

Question 22

Adenosine diphosphate

Answer 22

Remaining molecule after part of ATP splits off.

Two phosphates left

Question 23

Glycolysis

Answer 23

Glucose from the diet is turned into ATP molecules and waste Carbon.
In cytosol it turns into pyruvate.

Question 24

Cytoskeleton

Answer 24

A network of slender strands of protein (called filaments and micro tubules) inside the cell. 1. Acts to scaffold inside the cell or give it strength. 2. Allow movement of cell parts, or change shape of cell.

Question 25

Selective permeability

Answer 25

Cell membranes allow entry and exit of some materials in ways other than through channels and transporters. These methods do not require energy.

Question 26

Passive transport

Answer 26

Entry and exit of substances without the use of energy. E.g. Water passing through lipid bilayer Lipid molecules can cross the bilayer without using surface receptors or active transport because the bilayer is fatty.

Question 27

Nerve cells (neuron)

Answer 27

A type of cell with a membrane, receptors and protein channels. Made up of cell body and nucleus, dendrites, axon, axon terminal.

Question 28

Function of neuron

Answer 28

Detect chemicals called neurotransmitters in the extracellular fluid. Converts this chemical information into electrical information, which is transmitted through the axon to other parts of the body.

Question 29

Neurotransmitters

Answer 29

Made through metabolism in body Neurotransmitters combine with protein receptors on the surface of dendrites. Many cells must fire at another cell to cause that cell to fire because a cell has insufficient neurotransmitter to generate an action by itself.

Question 30

Receptor-gated channel

Answer 30

Channel, neurotransmitter and receptor Receptors sometimes change shape when a neurotransmitter arrives, allowing protein channels attached to the receptor to open. These channels link the extracellular fluid with the intracellular fluid. Normally, the cell membrane separates the fluids, causing a difference in charge. More positive charged material exists outside the cell. The different in charge is a voltage. Its value is -70mV (millivolts) If enough neurotransmitters arrive, then enough channels will be open, so the voltage will be raised.

Question 31

Voltage-sensitive channels

Answer 31

These channels only open when the cell's voltage reaches -55mV, and specifically let through positive sodium ions. A massive influx of positive charge means the inner surface of the cell temporarily becomes more positive compared to outside.

Question 32

Action potential

Answer 32

Movement of a wave of electrical charge through the dendrites and soma and down the axon to the axon terminal.

Question 33

Myelin

Answer 33

A fatty substance surrounding the axon which speeds up the action potential. Gaps between myelin on axon are called 'Nodes of Ranvier'.

Question 34

Synapse

Answer 34

The gap that exists between the axon terminal and either another neuron, muscle, or gland. Most often, an action potential arrives at the axon terminal causing neurotransmitter release into synapse.

Question 35

Post-synaptic cell

Answer 35

Found on the other side of the synapse.

Question 37

Dendrites

Answer 37

Project from soma into extracellular fluid. | Increase surface area of receptive area of cell, allowing cell to be more sensitive.

Question 38

Excitatory neurotransmitters

Answer 38

Generate action potentials in other neurons. I.e., transmit signals. E.g. Acetylcholine

Question 39

Excitatory post-synaptic potential

Answer 39

EPSP | Each presynaptic neuron can excite the postsynaptic neuron only minimally, unable to cause an action potential alone.

Question 40

Spatial summation

Answer 40

Cumulative effect on postsynaptic cells of simultaneous EPSPs from multiple neurons. AND Cumulative effect on postsynaptic cells of simultaneous IPSPs from multiple neurons.

Question 41

Inhibitory postsynaptic potential

Answer 41

IPSP Presynaptic neurons alone inhibit the postsynaptic neuron only minimally, meaning none of the presynaptic neurons alone can prevent the postsynaptic firing.

Question 42

Temporal summation

Answer 42

When the presynaptic cell releases multiple packets of neurotransmitters, which, in combination add up to just enough neurotransmitter to cause an action potential in the postsynaptic cell.

Question 43

Inhibitory neurotransmitters

Answer 43

They can prevent a cell from firing an action potential. I.e., block signals. E.g. Gamma Amino butyric acid or GABA Causes an influx of chloride ion into the post-synaptic cell, which makes the inside of the cell more negative than normal. Thus reducing the possibility of an action potential.