B1 Flashcards
Bacterial cells are examples off…
the bacterial cell is an example of prokaryotic cells
What does a prokaryotic cell contain?
the prokaryotic cell contains
cytoplasm
Cell membrane
cell wall
Use of a magnitude
the use of magnification is used to give the idea of how big or small something is
How to find the difference in magnitude
Find the differences in magnitudes find the difference (-) the powers of 10
what does an Animal cell contain
5
Animal cell contains
- nucleus
- cytoplasm
- cell membrane
- motrochondria
- ribosomes
What does a plant cell contain
5
plant cell contains:
- nucleus
- cell wall
- vacuole
- chloroplast
- cytoplasm
what does a Nucleus do?
the nucleus contains all the genetic material and controls the activities
what does a cytoplasm do?
The cytoplasm is where all the chemical reaction takes place and is like a jelly substance
what does a cell membrane do?
Controls what goes in and out of the cell
what do the mitochondria do?
Mitochondria is where aerobic respiration takes place
What do the Ribosomes do?
Ribosomes are where protein synthesis place
What does the cell wall do?
The cell wall provides structure and is made of cellulose
what does the chloroplast do?
The chloroplast is a green substance that absorbs light for photosynthesis
what does the vacuole do?
the vacuole is made of cell sap and gives support
An electron microscope has a…
electron microscope has a higher magnification and travels in power
The benefit of using an electron microscope?
able to study in much detail (cells has a finer detail )
the disadvantage of electron microscope
the disadvantage of an electron microscope is that it’s more expensive
How to work out the MAGNIFICATION
Size of Magnification=
size of an image (dived) size of real obj
[image/ real]
When does the animal cell develope
animal cell develops at the early stages
why is the cell division restricted in a mature animal cell?
a mature animal cell is mainly restricted to repair and replace
when does a plant cell differentiate?
a plant cell differentiates throughout life
How often does cell division (binary fission) take place
cell division (binary fission) occurs every 20 minutes depending on the nutrients and temperature
to grow an uncontaminated sample of bacterial its necessary to work ____
to grow an uncontaminated sample work
aseptically
- in a lab and free of pathogens
what must be done when carrying out an uncontaminated sample?
make sure…
- petri dish= sterilised (free from bacteria)
- sterilised through a flame
- the lid of the petri dish to be opened as little as possible
- stored upside down
How to calculate the number of bacteria over a certain time
work out many times the bacteria has divided
1) multiply the starting number by 2
2) then multiply that number by 2 and so on
- x2 as many times the bacteria divided
is stem cell…
differentiated or undifferentiated?
stems cells are undifferentiated
where are stem cells from?
stem cells are from human embryos and can be cloned into most different human cells
where can Meristem tissue be found? and where does it differentiate?
Meristem tissue are in plant cell and can be differentiated in any plant cell
what are the potential risks of stem cells
stem cells have risks of transferring viral infections and people have ethical/ religious rejections.
stem cells can be used to produce clones quickly, what are the benefits?
prevent the extinction of plants and can produce large numbers of identical plants at once
name 2 gases that are exchanged in a leaf
Water, oxygen or carbon dioxide is exchanged in a leaf
What is the function of the alveoli
The function of the alveoli is for rapid transfer of blood and the REMOVAL of the carbon dioxide
what plant cell is used to absorb water from the soil?
root hair cell is used to absorb water from minerals
What is the function of xylem?
The function of xylem is to transport water into the plant
what is the function of the nerve cell?
The function of the nerve cell is to carry around electrical impulse from one part of the body to another
are chromosomes normally found in pair or triplets?
Chromosomes are found in pairs ( one from the mother and one from the father)
what is mitosis? what is it used for?
mitosis is the stage when the cells divide
it’s used to grow or replace damaged cells
What is meant by the “mean division time” of a bacterial cell
Mean of division= the average time for a cell to divide into 2
what does a stem cell have the ability to do?
A stem cell has the ability to become a different type of cell
Name a gas molecule that can diffuse through the cell membrane?
Oxygen and carbon dioxide can diffuse through a cell membrane
osmosis is a…
a) fully permeable membrane
b) partially permeable membrane
Osmosis is a partially/semipermeable membrane
What is active transport?
Active transport is the movement between a substance from a Lower to a HIGHER concentration using energy from respiration
Difference between ACTIVE TRANSPORT and OSMOSIS
A difference between active transport and osmosis is that…
- Active transport needs energy
- osmosis needs water
ACTIVE transport travels from a LOWER to a HIGHER concentration
OSMOSIS travels from a HIGHER to LOWER concentration
What do fungi have?
6
Fungis has a
the nucleus, cell membrane, cell wall, cytoplasm, ribosomes and vacuole
what does yeast cell contain?
4
Yeast cell contains
Nucleus, cytoplasm, cell membrane and a cell wall
Name 3 specialised cells
specialised cells:
Red blood cell - carries oxygen to blood tissue
Phloem cell - Transportation of sugar
Xylem cell - Transportation of water and minerals
What substances pass through cell membranes via diffusion?
5/6
The substance that passes through the cell membranes using diffusion is…
Oxygen, carbon dioxide, glucose, amino acids, water and nutrients
Cell division is another word for ——
Binary fission
