Grade 9 science electricity Part C: Short Answer (Thinking/Inquiry)

36. Draw a circuit diagram to represent each description below. ***You may do this on paper & send a picture.

a. An electrical cell connected to a closed switch, a light bulb, a motor, and a fuse in series. Add a voltmeter to measure  the potential difference across the light bulb. (3 marks)

b. An AC power supply connected to a resistor and a light bulb on separate branches of a parallel circuit. Also, this circuit contains a switch that can control each load individually, an ammeter measuring the current flowing through the  resistor, and a voltmeter measuring the potential difference across the light bulb. (3 marks)

What happens when an ammeter is set up in a parallel connection with the part of the circuit where you want to measure current?

(a) The ammeter gets a correct reading.

(b) The ammeter damages the circuit's voltage source.

(c) The ammeter reverses the current flow through the circuit.

(d) The ammeter creates a short circuit.

Part B: True or False? 

* Determine if each statement is true (T) or false (F).

12. _______ An element cannot be broken down into simpler chemical substances by any physical or chemical means.

13. _______ If an element is a gas at room temperature, it is likely to be a metal.

14. _______ Elements in the same period of the Periodic Table have varying (different) properties.

15. _______ Hydrogen is a clear, colourless gas that is highly reactive. Based on these properties, Hydrogen is

similar to the Halogens.

16. _______ The element Iodine is a shiny black solid at room temperature. Iodine is thus an example of a metal.

17. _______ Electrical advertising signs made of colourful glowing light tubes are often filled with elements from the  

halogen family.

18. _______ John Dalton proposed the idea of indivisible atoms.

19. _______ Experiments by J.J. Thomson showed that atoms contain neutrons.

20. _______ An atom with 16 protons, 16 electrons and 18 neutrons has a mass number of 50.

21. _______ Elements in group 15 of the periodic table all have 15 valence electrons.

22. _______ Chlorine has electrons in 3 energy levels.

23. _______ When copper is added to tin, the alloy bronze is created. Bronze is an example of a compound.

Part B: True or False? (K – 12 marks)

* Determine if each statement is true (T) or false (F).

12. _______ An element cannot be broken down into simpler chemical substances by any physical or chemical means.

13. _______ If an element is a gas at room temperature, it is likely to be a metal.

14. _______ Elements in the same period of the Periodic Table have varying (different) properties.

15. _______ Hydrogen is a clear, colourless gas that is highly reactive. Based on these properties, Hydrogen is

similar to the Halogens.

16. _______ The element Iodine is a shiny black solid at room temperature. Iodine is thus an example of a metal.

17. _______ Electrical advertising signs made of colourful glowing light tubes are often filled with elements from the  

halogen family.

18. _______ John Dalton proposed the idea of indivisible atoms.

19. _______ Experiments by J.J. Thomson showed that atoms contain neutrons.

20. _______ An atom with 16 protons, 16 electrons and 18 neutrons has a mass number of 50.

21. _______ Elements in group 15 of the periodic table all have 15 valence electrons.

22. _______ Chlorine has electrons in 3 energy levels.

23. _______ When copper is added to tin, the alloy bronze is created. Bronze is an example of a compound.

Atomic #

Mass #

Standard Atomic

Notation

Family Name

p+

n0

e-

What are prions?

In cell, there are subcellular organelles. They are not full organism. Prions are just proteins. They don't have any other macromolecules. Prions have capacity to form copies through replication. They replicate through free radical and chain mechanism. 

Doctor Stainly pruisne work on prions and show it's relation with disease called mad cow disease. ( This is neurodegenerative disease and responsible for harmful effects on brain).

In Australia sheep was infected with prions, caused scarpie disease in sheep. Organs of sloghed sheep were used in cow feedd. When cow consume feed, prions were transmitted to cow and cow start to show unusual behavior.

Symptoms of prions infection are like that of some disease 

1. Kurulyprosy
2. Insomnia
3. Dimensia

Detection of prions: Prions can be detected by Western bloting.

Normal prions:

Normal prions are present in our body. They don't have tendency to form rigid aggregate. They are quite less in number. They have following functions

1. Cellular differentiation
2. Store elemental surplus that is used in future
3. Memory enhancement

Molecular basis of prions:There is some difference in structure of Normal and abnormal prions.

1.  Normal prions have molecular weight 33-35KD while abnormal prions have molecular weight 27-30KD
2. In normal prions at position 178 amino acid aspartate is present while in abnormal prions at 178 position asparagine is present. 

Prions diagnosis and analysis:

1. Brain biopsy....in past for taking sample brain biopsy was used but now a days tonsils biopsy is used for sampling.

Immuno fluorescence:Biopsy sample is taken on slide and it is treated with antibody ( of abnormal prions) which is against normal prions. Speciality of antibody is that when it bind with abnormal prion it will glow. If we capture fluroscene it's mean abnormal prion is present in sample. As abnormal prion antibody was label with fluroscene probe. So patient sample will show fluroscene while normal sample will not show fluroscene.

Transmission of prions: Normally prions can't Cross specie barrier they transmitted through different ways. Like as formite

If a person is effected with prions and he has wound in head and his comb is used by another person so prions can be transferred to other individual. Comb is Carrier of prion.

Prions are very slow acting immune system can't destroy them.