cell structure - exam questions Flashcards
define organ
a group of tissues
define organ system
group of organs working together to perform one or more functions
examples of organ systems in animals
digestive system
circulatory system
explain tissue culture
growth of cells in vitro
conditions necessary for successful tissue culture of any two
sterile conditions and nutrients
applications of tissue culture of any two
skin grafting
plant breeding
explain why the image cannot be produced by a light microscope
mitochondria are too small to be seen using a light microscope
name one type of animal cell that does not have mitochondria
red blood cell
an animal cell will burst if placed in a concentrated sugar solution
false
organs are groups of tissues with a shared function
true
eukaryotic
contains a nucleus
prokaryotic
does not contain a nucleus
which image represents a plant tissue
B
give a reason the image represents a plant tissue
cell wall present
all cells joined to each other
identify structure Z
nucleus
when examining cells with a microscope, name a stain you used
iodine
when examining cells with a microscope, give one benefit of using a stain
make cells more visible
what is the actual width of this cell
0.005 cm
describe the steps taken to view these cells at x400
select x40 objective lens
use fine focus
adrenaline is secreted into the blood when experiencing a threat
true
plants are produces however they still need mitochondria
true
neurotransmitters are transported in the blood
false
a potato is a root modified to store food
false
tissue culture involves growing cells on a artificial medium
true
there are four bones in the middle ear
false
monocotyledonous plants are almost always herbaceous
true
name two types of animal tissue
epidermis and connective
tissue
a group of cells with the same function
how the epidermis is adapted
one layer thick
how is connective tissue adapted
increased synthesis
tissue culture
growth of cells in vitro
another tissue application
plant breeding
name a protein that has a fibrous structure
collagen
where in the human body would you expect to find collagen?
skin
give a role of a named mineral other than calcium which is required in plants
magnesium, growth
state two reasons why water is required by living organisms
regulates body temperature
carries nutrients and oxygen acts as a solvent
name the metallic element present in haemoglobin
iron (fe)
what type of food biomolecule may be identified by the use of benedict’s or Fehling’s solution
reducing sugar
name molecules labeled in the cell membranes A and B
A - protein
B - lipid
molecules can move through cell membranes through various processes. name two such processes
osmosis
diffusion
suggest a reason why the organelle involved in aerobic respiration is found in different amounts in different cells
cells need different amounts of energy
what term is used to describe organisms whose cells contain a nucleus
eukaryotes
what term is used to describe organisms that do not have nuclei?
prokaryotes
name an organelle other than the nucleus which contains genetic material
mitochondria
give two features of eukaryotic cells that distinguish them from prokaryotic cells
possess a nucleus and mitochondria
give one function of one named tissue found in plants
xylem tissue - transports water and nutrients from the roots to different part of the plant
give one function of one named tissue found in animals
connective tissue - provides support and protection to the body
state one way in which xylem tissue is adapted to carry nutrients from the roots
forms a continuous hollow tube
state one way in which connective tissue is adapted to provide support and protection to the body
has white cells to defend body and platelets to clot the blood
state two requirements for successful tissue culture
sterile conditions
suitable temperature and pH
when preparing animal cells for examination with a light microscope describe how you obtained a sample of cells
rubbed inside cheek with swab
what stain did you use on the sample
methylene blue
outline how you used the coverslip
at an angle to eliminate air bubbles
explain why the coverslip is needed
to protect the sample from drying out
describe how you examined the cells using the microscope
focus using coarse focus
state function of the coarse focus
to focus on sample
state a role of connective tissue
transports nutrients through diffusion
give two examples of the use of tissue culture
plant breeding and skin grafts
state the precise location of the cell membrane in plants cells
Immediately inside the cell wall
with what type of cell do you associate membrane bound organelles
eukaryotic
what corresponding term is used to describe bacterial cells?
prokaryotic
what does selectively permeable mean?
only some substances are allowed to pass through
why is diffusion alternatively known as passive transport
no or little energy required
osmosis may be described as a ‘special case of diffusion. explain why
movement of water
name the structure by which amoeba gets rid of excess water that had entered by osmosis
contractile vacuole
give two locations in a cell at which there is a selectively permeable membrane
chloroplasts and mitochondria
what is diffusion
movement of molecules from area of high concentration to area of low concentration
in the case of a named molecule, give a precise location at which it diffuses in the human body
oxygen passing from alveoli into blood
explain the biological basis for the use of high salt concentration in the preservation of food
it reduces water activity of foods prevents them from rotting
in the human diet zinc, iron and copper are examples of
minerals
the walls of xylem vessels are reinforced with
ligin
where in a cell would you expect to find phospholipids
membrane
what vitamin is an example of a water-soluble vitamin
vitamin C
name a disorder associated with a deficiency of the vitamin c
scurvy
function of ribosome
protein synthesis
the function of cell membrane
selectively permeable
describe the difference in colour between the nucleus and cytoplasm when the stained cell was viewed under the microscope
cytoplasm paler
an example of a protein that has a structural role is
collagen
