Topic 1- Key Concepts Flashcards Preview

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Flashcards in Topic 1- Key Concepts Deck (43):
1

A eukaryotic cell is...

A cell with a nucleus
Eg.animal and plant cells

2

A prokaryotic cell is...

A cell with no nucleus
Eg. Bacteria cell

3

Animal cell structures

Nucleus, cell membrane, mitochondria and ribosomes

4

Plant cell structures

Nucleus, cell membrane, cell wall, chloroplasts, mitochondria, vacuole and ribosomes

5

Bacteria cell structure

Chromosomal DNA, plasmid DNA, cell membrane, ribosomes and flagella

6

Nucleus

Controls the activity of the cell and controls DNA

7

Cytoplasm

A gel like substance where most chemical reactions occur

8

Ribosome

The site of protein-synthesis

9

Mitochondria

Where aerobic respiration takes place.
Respiration releases energy that allows the cell to work.

10

Cell membrane

A barrier around the cell which holds the cell together and controls what chemicals enter and exit the cell

11

Cell wall

Supports and strengthens the cell

12

Vacuole

Contains cell sap which keeps the gives the cell support and keeps the cell firm

13

Chloroplast

Site of photosynthesis which makes the plant food
Contains a pigment called chlorophyll which makes the plant green

14

Plasmid DNA

Contains genes for things like drug resistance

15

Flagellum

Moves the cell away from toxic substances and towards oxygen

16

Chromosomal DNA

Controls cells activity and replication

17

Sperm cell adaptations

Acrosomes...contains enzymes which digest the egg cell membrane
Nucleus...only contains 23 chromosomes (haploid)
Lots of mitochondria...provide energy in ATP form from aerobic respiration for the sperm to swim
Tail...to swim to the egg cell

18

Egg cell adaptations

Nucleus...only contains 23 chromosomes (haploid)
Nutrients in the cytoplasm...provides energy for the egg to grow and divide when fertilised
Cell membrane...changes when the first sperm enters the egg to prevent other sperm cells entering

19

Ciliates Epithelial cell adaptations

Cilia...hair like structures which move substances in the body, they. Are covered in cell membrane and contain strands of a substance that can contract and cause waves of movements
Eg. Lungs- move and waft mucus
Eg. Fallopian tubes (oviducts)- waft egg cells towards the uterus

20

Coarse focus

Moves the stage or to aid focussing

21

Fine focus

Moves the stage (small amounts) to aid focussing
(Further down the microscope)

22

Mirror

Reflects light from the light source up through the stage

23

Objective lens

Magnifies the specimen (makes the specimen appear larger)

24

Stage

Supports and positions the slide for focusing

25

Magnification equation

Magnification = image size / actual size

26

Another magnification equation

Magnification = length of scale bar / length the bar represents

27

Magnification calculations

1m/1000 = 1 millimetre
1mm/1000 = 1 micrometer CELLS
1ym/1000 = 1 nanometer (the micrometer symbol isn’t right) PARTS OF CELLS
1nm/1000 = 1 picometer

28

Magnification is...

Resolution is...

The degree to which the size of an image is larger than the object itself, expressed as X1000 etc.

The ability to see (two) objects (that are close together) as separate objects and see detail

29

Where do enzymes act in the digestive system

Mouth, stomach and small intestines

30

Why do only protease enzymes work in the stomach

Protease enzymes can tolerate a lower pH. The stomach has hydrochloric acid (to kill pathogens)

31

Why enzymes are needed for digestion

Enzymes break down larger food molecules (eg.lipids) into small molecules (eg.fatty acids and glycerol)

32

LOOK AT TESTING FOR BIOLOGICAL MOLECULES

Pg.19 IN REVISION GUIDE AND LOOK IN SCHOOLBOOK FOR TABLE TO HELP

33

Describe...
Increasing temperature effects on enzymes

As temperature increases the rate of reaction increases (include date temperatures if included)
The rate is optimum at ...
Above the optimum temperature the rate of reaction decreases

34

Explain ...
Increasing temperature effecting enzyme

This is because as the temperature increases enzymes and substrate molecules gain kinetic energy and successfully collide more frequently... this resulting in more enzyme substrate complex being formed and more products being made
After optimum temperature rate of reaction decreases because the increased temperature denatures the enzyme which means...
The active site has changed shape this means that no ESCs will form and no product will be made

35

Describe
Increasing pH effects enzyme

As pH increases the enzyme activity increases
The enzyme activity is optimum at
Above the optimum temperature the enzyme activity decreases

36

Explain ...
Increasing pH effects enzyme

This is because as Ph increases fewer active sites are denatured, more ESCs from and more product is made
After optimum temperature the increasing pH causes the enzyme’s active site to denature and therefore fewer ESCs form and less product is made

37

Describe
Increasing substrate concentration effect on enzymes

As the pH substrate concentration increases the rate of reaction increases until an optimum substrate concentration of...
Above this optimum substrate concentration the rate of reaction stays the same/ does not change at the value of...

38

Explain...
Increasing substrate concentration effect on enzymes

This is because as the substrate concentration increases, more successful collisions occur between enzyme and substrate molecules which means more ESCs are formed and more product is made
At the point of saturation the rate of reaction is at a maximum because all the active sites are being used

39

Active transport is...

Substances move from a dilute to more concentrated solution (from low to high concentration)

Requires energy made from respiration in the mitochondria
Eg. Minerals taken into root hair cells from the soil

40

Diffusion is...

The movement of molecules from an area of high concentration to low concentration
Doesn’t require energy
Molecules move in random directions
Happens in gases and liquids
Osmosis is diffusion in water

41

Osmosis is...

The random movement of water molecules from an area high water potential to an area of low water potential through a partially permeable membrane

42

Osmosis in potatoes

Roughy, as the concentration of salt solution increases the change in mass also increased

43

Hypotonic is....
Isotonic is...
Hypertonic is...

...water solution-gain
...same water potential
...salt solution-loss