bio lab practical 1

Scatter Plot

• focus is showing correlation between 2 variables

• data is increasing numercial values

Histogram

• mulitple variables

line graph

• focus is showing change over time

• numerical values for variables

bar graph

• focus is frequency distribution

Acidic solutions

• more H+>OH- ions

• less than 7

base solutions

• more OH->H+ ions

• more than 7

neutral solution

• OH-=H+

• 7 is neutral

What are the effects of adding a buffer to a solution?

the buffer resists change in solutions pH

Ion

atoms with a charge

• positve charge: protons>electrons

• negative charge: electrons> protons

electrolyte

conduct electrical currnet & maintain physiological function in cells

chemical reactions

when 2+ elements form new substances/compound breaks into diff elements

Does Na+ mean sodium has lost/gained an electron?

Na+ means sodium lost an electron

Would you expect glucose to form ions when it’s dissolved in water? Why/why not?

Glucose doesn’t form ions bc its a covalent bond therefore has no electrical charge + its a nonelectrolyte

What type of bond is produced between + and - ion?

ionic bond

What characteristics of a compound enable you to predict whether it’s ionic or covalent?

By knowing it the compound’s elements are metal or nonmetal.

• ionic: metal + nonmental

• covalent : nonmetal + nonmetal

What characteristics of a compound allow you to confirm experimentally if it’s ionic/covalent?

Seeing if it can conduct electricity when dissolved in H2O.

• ionic bonds conduct electricity

Polar molecule

molecule that has a partial charge

What bond contributes to the cohesive properties of water

hydrogen bond

Solubility

how well a substance can dissolve in a solute

solvent

solution that dissolves

solute

what gets dissolved

solution

mixture of solute + solvent

Describe how to make a wet mount

1. place drop of water on microscope slide & place specimen

2. lower coverslip onto specimen

3. blot excessive water

4. view under lens

things to be done prior to returning microscope

• make sure lowest power objective is on

• lower stage

• light is turned off

• cover & get checked off

Diffusion

random movement of molecules from high to low concentration gradient w/o use of energy

Osmosis

diffusion throu semipermeable membrane, w/o use of energy

Factors impacting rate of diffusion

• size of concentration gradient

• smaller mass of molecule

• high temperature

How does water move in/out of semipermeable bags for both plant & animal cells.

• hypotonic solutions: O2 moves into the cell [less concentration in beaker]

• hypertonic: O2 moves outside from cell to beaker [high concentration in beaker]

• isotonic: remains same

What happens to plant cell in isotonic, hypotonic, and hypertonic solution?

• isotonic: cell remains same

• hypotonic: cell is firm

• hypertonic: plasmolysis

What happens to animal cell in isotonic, hypotonic, and hypertonic solution?

• isotonic: cell remains same

• hypotonic: cell is bursts/swells

• hypertonic: cell shrinks

enzyme

protein that speeds chemical reaction

substrate

molecule which enzymes act on

active site

part of enzyme where the substrate attaches —> allowing reaction to occur

How do enzymes act as catalyst of reactions? How do they affect activation energy?

1. Enzymes speed up chemical reactions, by lowering activation energy needed for the reaction to occur.

2. Enzymes lower activation energy:

• weaken bonds

• bring substrate in right position

How does the concentration of an enzyme, temperature, and pH afect rate of reactions? How do they relate to denaturation & binding of an enzyme to it’s substrate?

All of these factors increase how fast the reaction time is, because the enzyme has more active sites where it can bind to the substrate.

• too much of these factors can cause denaturation decreasing fast reaction time

denaturation

when protein unravels causing it to lose it’s function

What is consumed in Aerobic respiration?

O2, glucose

What is produced in Aerobic respiration?

CO2, H2O, ATP

What was the lime soda used for in detecting Aerobic respiration in beans?

removes any O2 in the flask

Know how temperature affects anaerobic respiration

Temperature impacts reaction time

• lower temperature, it slows reaction time

• high temperature, it leads to faster reaction or denaturation