Bio transition test Flashcards
what elements make carbohydrate molecules
carbon, hydrogen and
oxygen
What does hydrolysis do
breaks down polymers into monomers
What happens in a condensation reaction
2 monosaccharides joined to make disaccharide and release a molecule of water.
glucose+fructose
sucrose+water
glucose+galactose
Lactose+ water
glucose+glucose
Maltose +Water
formula for monosaccharides
(CH2O)n
what are lipids made of
carbon, hydrogen and oxygen
what do triglycerides contain
a molecule of Glycerol with 3 fatty acids
what are phospholipids made of
2 fatty acid chains and a phosphate group
what are proteins held together by
peptide bonds
what do amino acids contain
Hydrogen, Oxygen, Nitrogen and Carbon.
Primary structure of proteins
amino acids that are held
together by peptide bonds into a polypeptide
chain
SECONDARY STRUCTURE of proteins
The polypeptide (protein) chain can then coil or
fold into pleats which are held together by
weak hydrogen bonds.
TERTIARY STRUCTURE of a protein
Enzymes have a further folding held together
with hydrogen bonds as well as stronger ionic
bonds and disulphide bonds. If the structure is
almost spherical it is called a globular protein.
give an example of a globular protein
enymes
define anabolic
build substrates up
define catabolic
breaks substrates down
What is DNA made up of
pentose sugar, phosphate and nitrogenous bases forming
a NUCLEOTIDE.
define gene
A
section of DNA that codes for a protein
DESCRIBE Protein synthesis
transcription-happens in the nucleus
base of sequence of a gene is copied into a complimentary template molecule (mRNA)
—> mRNA passes into the cytoplasm
Translation
mRNA molecule attaches to ribosome, amino acids are brought to the ribosome by carrier molecules (tRNA-anticodon is complementary to the mRNA.)
At the opposite end there are three unpaired bases which code for an amino acid.
The
amino acid is brought in to form a peptide bond with the amino acids brought in by the
previous tRNA. This forms a polypeptide chain which will form hydrogen and ionic and
disulphide bonds to form the unique protein.
ribosome reads triplets of bases on the mRNA and uses it to join together the correct amino acids in the correct order.
what is meant by substitution in mutation
Some bases may change to a different
base
When glucose is broken down by aerobic respiration it releases…
energy, adenosine triphosphate (ATP)
OUTLINE THE STAGES OF Aerobic respiration
- Glycolysis- in the cytoplasm and converts
glucose into two 3 carbon molecules called PYRUVATE. - Pyruvate passes into the matrix of the mitochondria , to carry out a link reaction forming acetyl CoA
- Acetyl CoA passes into the Krebs cycle the reduced products passing into the electron transport chain in the
process of oxidative phosphorylation to form ATP and the waste products carbon dioxide
and water.
Outline Anaerobic Respiration
Glucose is converted into pyruvate through glycolysis in the cytoplasm.
does not go into the mitochondria
anaerobic respiration products in animals and plants
plant- co2 and alcohol
animals-lactic acid
The Light microscope
*Magnification
*1500
Electron microscope magnification
50000*
+better resolution
how much bigger are eukaryotes compared to prokaryotes
Prokaryotes like
bacteria are roughly
a tenth the size of
eukaryotic cells.
what is the cell surface membrane made of
PHOSPHOLIPID BILAYER
what do u call the double membrane of a nuclei
nuclear envelope
describe facilitated diffusion
Some particles are too large to fit through the phospholipid bilayer
and therefore require a carrier protein to assist. The protein carriers are within the bilayer,
and they change shape when they come into contact with a specific molecule
describe active transport
Moves substances from an area of low concentration to an area of high concentration against the concentration gradient
types of proteins in facilitated diffusion
Channel proteins and carrier proteins
roles of Phagocytes
type of white blood cells that engulf pathogens carrying foreign antigens
and destroying them.
what are antigens
molecules on the surface of a pathogen that
marks it as foreign to the body. All cells including human
cells contain antigens on their surfaces.
name the 2 different types of lymphocytes and their purpose
B-cells/B-lymphocytes are white blood cells that produce antibodies that bind to antigens
T-cells/T-lymphocytes s are white blood cells that communicate between phagocytes and
B-cells. When a phagocyte engulfs a pathogen, it signals to the T-cells that a foreign object
has been found. The T-cell then activates the B-cells to produce antibodies.
what do vaccines contain
contain antigens from inactivated or dead
pathogens
Adaptations of large organisms in order to have quicker exchange
- Folded to increase the surface area to volume ratio for a faster exchange.
- A good blood supply to maintain the concentration gradient.
- One cell thick (thin) to reduce diffusion distance.
Adaptations of lungs
*alveoli are folded
*alveoli have a flattened layer of epithelial squamous cells -shortens diffusion distances
*walls of alveoli are fully permeable
outline the process of inhalation
Intercostal muscles contract lifting rib cage up and out
diaphragm contracts and pulls downward
the lungs expand and air is sucked in
outline the process of exhalation
intercostal muscles relax
diaphragm relaxes
the ribs fall downward and inward
diaphragm back into the dome shape, squeezing lungs and pushing air out
upper mesophyll
contains
Palisade cells which
are packed with
chloroplasts to absorb
as much energy from
the sun as possible for
photosynthesis.
The lower part of the
spongy mesophyll
layer
contains
air spaces to facilitate
the diffusion of gases
into the cells and out of the cells.
upper epidermis
covered by a waxy cuticle to prevent water loss
The lower
epidermis
specialised pair of cells called the GUARD CELLS. The guard cells have an
uneven thickening in the cell wall which causes the cell to bend and open up a hole in the
lower epidermis called the STOMA. The stoma allows the water vapour to move out of the
leaf into the environment (transpiration) and carbon dioxide to move into the leaf.
what is pulmonary circulation
carries deoxygenated blood from heart to lungs and oxygenated blood back to the heart
what is systemic circulation
carries oxygenated blood from the heart throughout the body and deoxygenated blood back to the heart.
properties of arteries
thick layer of elastic tissue and smooth muscle. The elastic
walls stretch when the heart contracts and the elastic tissue
recoils to maintain the pressure.
properties of capillaries
single layer of endothelial cells. The arteries subdivide into
arterioles which further divide into thousands of capillaries. The capillaries come into close
contact with body cells providing a huge surface area to volume ratio and a short diffusion
distance for the exchange of oxygen, glucose,
carbon dioxide, urea and other substances.
properties of veins
capillaries start to come back
together forming venules and then veins. Veins
carry blood back towards the heart. Blood is at a
lower pressure and therefore do not need such a thick layer of elastic tissue or smooth
muscle. The veins contain valves to prevent the blood flowing backwards.
the pace maker is also known as
SINO-ATRIAL NODE
outline the cardiac cycle
a. cardiac diastole- all chambers are relaxed the blood flows into the heart
b. atrial systole, ventricular diastole-atria contract, pushing blood into the ventricles
c. Atrial diastole, ventricular systole- after the atria relax the ventricles contract, pushing blood out of the heart.
name the 3 ways water passes through the root
the symplast pathway
the apoplast pathway
the vacular pathway
outline the symplast pathway
water moves
from root cell to root cell through the
cytoplasm.
outline the apoplast pathway
water moves
through the cell wall, not passing over the
cell membrane, carrying minerals with it
through a process called MASS FLOW.
outline vacuolar pathway
water moves from root cell to root cell via the cytoplasm and
the vacuole. Water moves out of the leaf by diffusion into the environment.
define A species
a group of organisms that have similar characteristics and can reproduce to give
fertile offspring.
what are organisms organised based upon
Organisms are arranged based on their
similarities and differences and are placed into
classification hierarchies.
