1. Made by: Khaled alanazi
Virtual Lab questions
Made by: Khaled alanazi
All Virtual lab questions and answers are included (5 topics)
Summarization of experiment introductions
Key points of each topic
Only for review and it’s not a full reference to study for the exam from.

2. Contents Resting membrane potential
Chemical synaptic transmission & neurotransmitter release
The muscle twitch & the latent period
Carbohydrates digestion
Protein Digestion

3. Resting membrane potential
Receptor potential (generator potential):
Graded response to a stimulus that might be Depolarizing or Hyperpolarizing
Synaptic potential:
The difference in voltage between the inside & outside of a postsynaptic neuron, it’s the incoming signal of a neuron (excitatory or inhibitory).
Action potential:
The change in electrical potential associated with the passage of an impulse along the cell membrane.
Resting membrane potential:
Is membrane voltage of cell not producing impulses; about is –65 to –85 mV of most cells.

4. Resting membrane potential

5. Resting membrane potential

6. Resting membrane potential

7. Chemical synaptic transmission & neurotransmitter release
The major function of the nervous system is communication
The axon conducts action potential from place to another
Axon terminal releases packets of chemical neurotransmitters
Neurotransmitters acts on: Paracrine, Autocrine, and endocrine (as a hormone)
Released by exocytosis and diffuses across synaptic cleft
Neurotransmitters often binds to membrane receptor protein on target cell
Neurotransmitters leads to opening or closing membrane Ion channel and changing membrane potential on the target cell

8. Chemical synaptic transmission & neurotransmitter release
Chemical synapse: the region where the Neurotransmitters is released from one neuron and binds to a receptor on a target cell
Postsynaptic potential or (Synaptic potential): is the change in membrane potential of the target cell.
Exocytosis of synaptic vesicle is triggered by an increase in Ca+ ions in axon terminal
Ca+ enters from outside the cell through Ca+ channels that are opened by the depolarization of the action potential

9. Chemical synaptic transmission & neurotransmitter release

10. Chemical synaptic transmission & neurotransmitter release

11. Chemical synaptic transmission & neurotransmitter release

12. Chemical synaptic transmission & neurotransmitter release

13. The muscle twitch & the latent period
Motor unit: Consists of a motor neuron and all of the muscle fibers it innervates
Neuromuscular junction: Is a chemical synapse formed by the contact between a motor neuron axon terminal and a muscle fiber’s plasma membrane
Motor endplate: Folds at the muscle fiber plasma membrane to increase the surface area
End plate potentials (EPPs): the depolarizations of skeletal muscle fibers caused by neurotransmitters binding (Ach) to the postsynaptic membrane in the neuromuscular junction
Ach: Results in Graded depolarization of the muscle plasma membrane (end plate potential)
End plate potentials: Triggers the events that leads to muscle contraction
Excitation–contraction coupling: is the connection between the electrical action potential and the mechanical muscle contraction

14. The muscle twitch & the latent period
Muscle twitch: is a motor units response to a single action potential of its motor neuron and has 3 phases:
The latent period: is the first few milliseconds following stimulation when excitation contraction coupling is occurring (Ca+ release from SR, no muscle tension is measurable, and cross bridges are inactive)
Contraction period: cross bridges are active, from the onset to the peak of tension development, and the myogram tracing rises to a peak
Relaxation period: is the time during which tension is removed from the muscle, initiated by reentry of Ca+ into the SR.

15. The muscle twitch & the latent period

16. The muscle twitch & the latent period

17. The muscle twitch & the latent period

18. The muscle twitch & the latent period

19. Carbohydrates digestion
Starch is hydrolyzed to Maltose by SALIVARY AMYLASE
Amylase is produced by salivary glands
with a positive control: All the required substances are included and a positive result is expected
Sometimes negative control is included, and a negative result is expected
Negative control with a negative result validates the experiment
Negative control is used to determine if there is any contaminating substances in the reagent
When a positive result is produced and a negative result was expected, it’s means there is one or more contaminating substances in the reagent

20. Carbohydrates digestion
with amylase activity: starch decreases and sugar increases
The IkI assay detects: the presence of starch
The benedict’s assay: the presence of reducing sugar( glucose or maltose) which are the products of starch
IkI: turns blue –black in presence of starch
Benedict’s: green to orange in presence of maltose
Amylase: enzyme that digest starch
starch: complex carbohydrate
Maltose: disaccharide

21. Carbohydrates digestion
Freezing has no effect on amylase
boiling of amylase will cause denaturation of the enzyme
amylase optimum pH is 6.7–7.0
The substrate of amylase if amylose and the subunit product is glucose

22. Carbohydrates digestion

23. Carbohydrates digestion

24. Carbohydrates digestion

25. Protein digestion
Peptides: two or more Amino acids linked together by a peptide bond
Polypeptide: Peptide chain containing 10 to 100 A.A
Protein: Large peptide chain (more than 100 A.A) or multiple peptide chains
Pepsin: Produced by Chief cells (Peptic cells) of the stomach to hydrolyzes peptide bonds.

26. Protein digestion

27. Protein digestion

28. Protein digestion

29. Best of Luck