Zusammenfassung der Ressource
biology KS4 revision
- cells
- animal cells
- nucleus
- contains genetic
material which controls
the activities of the cell
- cell membrane
- acts as a barrier
and controls what
goes in and out of
the cell
- mitchondria
- where most energy is
released through
respiration
- ribosomes
- where protein
synthesis takes
place
- cytoplasm
- most chemical
processes take place
here, controlled by
enzymes
- plant cells
- cytoplasm
- nucleus
- cell membrane
- permanent vacuole
- filled with cell
sap to help
keep the cell
inflated (turgid)
- cell wall
- helps support
the structure
of the cell
- chloroplast
- contains chloryphyll
which uses light
energy for photo
synthesis
- bacteria cells
- single celled organisms
- different structure to
plant and animal
cells
- has a cytoplasm,
cell wall and cell
membrane
- genetic material is
not in a distinct
nucleus
- yeast cell
- same as
bacteria cell
- also has a nucleus
- leaf cell
- absorbs light
energy for
photosynthesis
- regular shaped
plant cell
- packed
with
chloroplasts
- root hair cells
- absorbs water and mineral
ions from surrounding soil
- diffusion
- disolved
substances have
to pass through
the cell
membrane to get
in or out of the
cell
- diffusion
allows this
to happen
- diffusion takes
place when
particles go from a
high concentration
to a low
concentration
- this only
happens when
the particles are
free to move
- this happens
often with gases (
how a smell
travels from one
area of the room
to another)
- from the lungs oxygen particles
move from the alvioli air space into the
bood circulating around the lungsto
be able to be taken around the body
where they are needed
- tissues, organs and organ
systems
- organs in animals
- multicellular organisms
usually have differenciated
cells that have specific
functions
- tissues are groups of
similar cells
- organs cosist of
different tissues
working together to
carry out a particular
a function
- organ systems
consist of different
organs
- different organ
systems work
together to
create an
organism
- some organs
consist of a
number of
different tissues
- muscle tissue
- contracts, creating movement
- glandular tissue
- produces
substances such
as enzymes and
hormones
- epithelial
- covers most parts of the body
- the body has
several organ
systems
- the respiritory system,
the digestive system,
the reproductive system,
the nervous system
- liver
- produces bile
- stomach
- digests foods
- pancreas
- produces enzymes
- small intestine
- digest and absorb souluable food
- large intestine
- absorbs water from undigested foods producing feceas
- organs in plants
- plants are
multicellular
organisms like
animals
- they also
contain
differenciated
cells, tissues
and organs
- mesophyll carries out
photosynthesis
- xylem and phloem transport
substances around the plant
- sections of a leaf
- waxy cuticle
- protects the leaf
without blocking out
sunlight
- upper and lower
epidermis
- protecitve layer of cells
which allow more light
through
- paliside cells
- absorb the light to allow
ohotosynthesis to take
place
- spongy messophyll
- irregular shaped layer of cells
with airspaces
inbetween to allow
carbon dioxide to
diffuse into the cell
- photosynthesis
- these sections of the
leaf allow
photosynthesis to take
place
- factors affecting
the rate of reaction
- temperature
- on a graph the line will increase
then once it has got to the
limiting point the line will then
fall back down
- carbon dioxide
concentration
- on a graph the
line will increase
then level off
- light intencity
- photosynthesis is a
chemical change
- carbon diocide + water -----> glucose +oxygen
- light intensity
- some gluecose is used for
respiration while most is
converted into starch and
stored
- organisms and their enviroment
- the distribution of living
organisms in a particular
habitat may be due to
physical factors
- these physical factors include
- the temperature
- amount of light available
- availability of water
- availability of nutruents
- availability of oxygen
and carbondioxide
- enviroment
- all the conditions
that surround a
organism
- ecosystem
- the comunity and
the habitat which
it lives in
- habitat
- place where it lives
- population
- all the members of a
single speciece that
live in that habitat
- community
- population of
different organisms
that live together in
the same habitat
- collecting quantitive data
- use a quadrat to collect
a sample of data
- this method is used as it
is not always possible to
collect an entire
population of a particular
organism in its habitat
- this must be placed
rendomly to ensure a
representative sample is
taken
- the more results taken
and put together the more
reliable the results
become
- from the results you can
calculate the mean,
median and mode
number of organisms in
that habitat
- proteins and their function
- protain molecules are
long chains of smaller
molecules named amino
acids
- protein molecules
are brocken down by
protease
- protease can be used
to pre digest food in
baby food
- produced in the small
intestine, stomach,
pancreas
- enzymes are
biological catalysts
- they speed up the rate
of chemical reactions
- they are proteins that fold up into cpmplex shapes to allow
smaller molecules to fit in to them. the place where the
substraits fit into the enzyme is called the active site
- the enzyme can
break a large
subsrtare down or join
to small substrate
molecules together
- enzyme molecules can become denatured if the
temperature of their envioroment increases above
37degreeese c.
- if an enzyme has been denatured the active site has become
miss shaped and therefore cannot breake down the correct
molecules
- fat molecules are
broken down into
glycerol
- produced in the
pancreas and
small intestine
- lipase is used in
manurfactoring for
biological detergents
- starch molecules are
broken down into sugars
by amylase enzymes
- produced in the
salivary gland,
pancreas and small
intestine
- enzymes in the stomach
work best in acidic
conditions the acid in the
stomach is hydrochloric
acid
- enzymes in the small intestine work best in alkali
conditions. to nutralise the food so that it can
becom an alkali once it has left the stomach the
liver produces a substancece called bile that is
stored in the call bladder
- respiration
- aerobic
- respiration with
the use of oxygen
to produce energy
- oxygen + glucose --> carbon dioxide+ water ( +energy)
- anaerobic
- respireation
with the
absence of
oxygen
- glucose--> lactic acid (+ little energy)
- this lactic acid can lead
to muscle fatigue ( state
of total mental and
physical exahusion due to
extreme exercise)
- incomplete breakdown of glucose
- oxygen dept
- the amout of oxygen
needed to oxydise lactic
acid into carbon dioxide
and water
- this happens
because the
breakdown of
glucose is
incomplete
- respiration
releces energy
for cells from
glucose
- energy is
produced from
glucose
- cells store glucose as
glycogen and can be
turned back into glucose
during exercise
- during exercise the
muscles cells respire
more rapidly than
they would when at
rest
- now, oxygen and
glucose must be
delivered to the
cells more quickly
- and the waste
product carbon
dioxide must
be removed
more quickly
- to solve this the hart
rate increases to
increase the blood
flow around the body.
and the breathing rate
increases to increase
the rate of gaseous
exchanges in the
body
- cell division and inheritance
- DNA and Cell division
- DNA
- large and
complex
meolecules
- carry the ginetic
code that
determins the
charicteristics of
living organisms
- each persons
DNA is uniqu
- Genes
- this is a short
section of DNA
- each gene codes for
a specific protein by
specifying a
particular order in
which amino acids
need to be joined
together
- Chromosomes
- the cells nucleus
contains chromosomes
made from long DNA
molecules
- 23 pairs of
chromosomes
in a body cell
- body cells divide
by a process
called mitosis
- the genetic information is
copied and the cell spits
into two daughter cells, this
process then repeats
- mitosis occurs during
growth, and to produce
replacement cells
- gametes are sex
cells, they contain
one set of genetic
information
- the type of cell
division that produces
gametes is mieosis
- when the male gametes and femail
gametes join together in fertilisation
the two single sets of chromosomes
join together to greate 23 pairs of
chromosomes which provide the
genetic information needed
- cells divide twice
to form four
gametes
- most animal cells
are specialised for a
particular function
and these functions
cannot be changed
- stem sells
- stem cells can be made
to differenciate to form
different types of cells,
such as nerve cells
- human stem cells can also be used
from embryos and bone marrow
- genetic variation and genetic dissorders
- there are two types of
alleles, dominant and
ressessive
- speciation