4 Flashcards
deamination
proccess of removing an amino acid frm a molecule.
mesentery
a fold of membrane that attaches the intestine to the abdominal wall and holds it in place
for people with diabetets, their pancreas fails to produce insulin or their cells irreposnive to insulin. Why?
these outcpomes are the result of te failure of a sensor and their cells to become irresponsive to insulin
diabetes rsults in bodys failure to achieve homeostasis. define homesatsis with specific reference to this disease
homestasis in regards to diaetes refers to the maintance of blood gluose levels within a narrow range for optimal function
with reference to the glomerlus, explain how kidney damage may lead to microalbumrinina
high blood pressure meanst hat blood is filtered through the glomeularus with great force which could cause small tears in the capillaries comprising the glomeuleurus and damaging it.
besides the glomeulrus, what other parts of the nephron may result in microalbumrinia
proximal convulated tubule
how does hyperthyrdoisim result in weightloss
hyperthyrdoism results in an overporuction of hydroid hromoens wich regulate body systems. An excessive amount of these hormones can increase metabolic rates in the body resulting in weight loss
why would a leaf be rolled
drought and high temeprature
one exmaple of an effector is the smooth msucle in peripheral blood vessels
explain how this effector brings a decrease in body temperature
the smooth muslce tissue within te perihpal blood vessels releases,allowing vessels to dilate. This increasesthe volume of blood close to the surface of the skin, leading to heat loss.
what are the 3 parts of the large intestine
cecum
colon
rectum
hydrchoirc acid do
kills pathoens that enter the stomahc
how would ulcers befound
hydrochlroci acid kills pathogens and mucus membanres portcets the stomach lining from being digested by pepsin and form hydrochloric acid.
pyloric sphincter
muslce that seperates the duodenum from the stomach and holds the food in the stomahc until it is broken down and releases the food
bicarbondate
neutrlaises acidic food frm the stomahc the bring hte optium PH to 7.6
Trypsin
protein digestiing enyzme that digests proteins into amni acids
pancreal duct and bile duct function
pancreal duct and bile duct function
A
pathway that allows secretiosn frm the pancreas into the small intestine
bile duct pathya where bile is secreted from the liver into the small inteistne
how do hervbires have adaptions that allow them to digest celluose
caecum contains bacteria that proudce na enznyme called cellulase which breaks down cellulose
function of mucus
acts as a protective layer for the stomach against its own secreted enzymes and acids.
The pyloric sphincter is damaged. What is the issue?
if they pylorci sphisnter is stomach the food will not be digested intothe stomach it will move directly from the stomach into the dondedmum, therefore food will not be digested properly and doneudmumwill be directly exposed to the hydrochloric, this will cause ulcers
A herbivore such as a rabbit has a diastema instead of what? What is the purpose of this?
A herbivore such as a rabbit has a distema instead of canine teeth. As these animals lack canines which are required to tear food, the distema helps the other teeth work together to cut food. Distaema also allows the food to contiousnyi pass intothe oriel cavity whilst the herbivore is chewing.
mesentery
a membrane that attaches the abodmiaml area to small itnesitne, therefore keeps the digetsive system in place.
glycorptoein
sends and recievees signals and is involved in cell to cell adhesion
Explain why scientists describe the plasma membrane as a ‘fluid mosaic’.
The plasma membrane is fluid because the phospholipids and other molecules can move around – they are not stiff or held in one place.1The plasma membrane is mosaic because many different molecules are embedded in the membrane.2
Novel nanomaterials called ‘nanomedicines’ are being developed to diagnose and treat disease. To work, nanomedicines must enter a cell and interact with particular sub-cellular molecules. Nanomedicines gain entry into target cells through endocytosis.
Some scientists are concerned that after endocytosis, the nanomedicine may be destroyed by the cell. Explain how this might occur.
Lysosomes may fuse with the vesicle containing the nanomedicine.1Lysosomes contain enzymes which may destroy the nanomedicine.2
Explain the change occurring inside the guard cells and epidermal cells that leads to the net movement of water.
A
Guard cells become less turgid when water leaves, which occurs through osmosis.1For osmosis to occur quickly, ion channels open in the membranes of guard cells, and this leads to epidermal cells becoming hypertonic relative to guard cells.2Water will move from the area of low solute concentration (guard cells) to high solute concentration (epidermal cells).3
The concentration of potassium ions, K+, in human blood plasma is approximately 4 mM. In the cytoplasm of red blood cells the concentration of these ions is around 100 mM. Explain how this difference in concentration is maintained.
This difference in concentration is maintained using active transport.1In active transport, ATP is used by specific protein pumps to transport K+ against its concentration gradient into the red blood cells, increasing the concentration of K+ in the cell. K+ is charged so cannot easily diffuse across the plasma membrane, meaning the cytoplasm remains hypertonic to the blood plasma in terms of K+
what is the G1 phase involved in, what is being duplicated, what happens to the volume of cytsol in the G1 phase, why are proteins created in the G1 phase, why are orangalles replicated in the G1 phase,
Involved in the growth of a cell
all cells are duplicated besides chromsomes
volume of cystol increases
Proteins are created for DNA replication
organelles are replicated to prepare for replication
G1 phase
process to make the cell complete again and duplication of celluar contents besides chromsomes
G2 phase
monitors DNA duplications for growth and preparation for mitosis
METAPHASE-What happens to sister chromatids and chrosomes in metaphase
Spindle fibres fully form and attach to the centromere of each sister chromatid
sister chromatids align along the equator
ANAPHASE-what happens to sister chromatids in anaphase and what forms annd what spilts
Sister chromatids are pulled by spindle fibres from the centromere to opposite sides of the cell
DNA spilts
Difference of cytokinesis in animals and plants
in the cytokinesis of animals Cleavage furrow develops and pinches the plasma membrane into two cells
in the cytookensis of plantsA cell plate first forms before separating into two cells
homologous chrosomem
a pair of chromosomes, with exact same DNA howeverv one chrosome is maternal and another paternal
what do spindle fibres do
they pull the chromosomes to opposite ends of the cell
what do spindle fibres do
they pull the chromosomes to opposite ends of the cell
Q
telophase
chromatin decondenses
nucela envelope starts to reappear
clevaeg furrow forms
2 new cells walls and cell membranes found
cell undergoes cytokinesis
prophase-
Nuclear envelope starts to disappear
Chromatin condenses
centrioles produce from spinlde fibres and migrate to oppostire sides of the cell
MAJOR STEPS OF APOPTOSIS:
1.Caspase enzymes are activated
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2.Organelles begin to breakdown
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3.The cell and nucleus shrinks and chromatic condesnses●
4.Blebbing of the plasma membrane occurs forming apoptotic bodies
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5.Apoptotic bodies are engulfed by phagocytes (immune cells).
APOPTOSIS:Mitochondria(intrinsic) pathway-
Process:
When DNA is damaged (radiation), the mitochondria releases a protein known as cytochrome c
Cytochrome c binds with proteins in the cytosol to activate caspase enzymes
When caspases are active, apoptosis begins.
Death receptor pathway what is
Signalling molecules called death ligands bind to death receptors on the plasma membrane, this causes capsace enxymes to become activated to start apoptosis
Inhibited apoptosis:
May result in unnecessary body parts after development eg. webbed feet and hands
Characteristics of cancer cells:
-Able to invade and spread
-resist cell death
-good blood supply
-evade tumours suppressors such as p53 gene
-able to replicate(immortal)
Excessive apoptosis:
may result in diseases and disorders such as Huntington’s disease, Alzheimer’s disease and Parkinson’s disease.
apoptosis and example
regulated/controlled programmed cell death
example would be apotposis removing flesh between webbed hands in the womb
What are the two major stages of apoptosis and what dothey iinclude
initiation-involves intrinsic and extrinsic pathway
execution-
**list whathappens in apoptoisis
what are cancer cells, how do they form and how do cancer cells spread
cancer cells form to genetic changes when a normal cell is transformed into a malignant cell
cancer cells spread by dividing uncontrollably and spreading to surrounding tissues.
An example of an essiental change that causes magliancy
