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82 Cards in this Set
- Front
- Back
Placing organisms in groups |
Kingdom -> phyla -> class -> order -> family -> genus -> species |
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Endoplasmic Reticulum (ER) |
- transports substances around the cell - inter-connected system of membrane-closed flattened channels -ER with ribosomes is ROUGH ER - NO ribosomes is SMOOTH ER |
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DEFINE ecosystem |
Biological unit comprising of the community living in a discrete region |
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Keystone species |
species that have a large role in the ecosystem |
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Competition |
INTERSPECIFIC: competition for resources in an ecosystem involving 2 species INTRASPECIFIC: competition for resources in an ecosystem involving some species |
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Taxonomy |
identifying, naming, describing and classifying organisms into groups |
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Biodiversity |
Total number of DIFFERENT organisms living in an area |
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Lysosomes |
- a sack containing about 50 digestive enzymes which break down bacteria - performs autophagy - breaks down non-functioning cells |
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3 levels of biodiversity |
1. species diversity 2. genetic diversity 3. ecosystem diversity |
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Chloroplasts |
- found in plant and algae cells - responsible for performing photosynthesis - has 2 membranes |
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Nucleus |
- in eukaryotic cells - membrane bound organelle containing DNA |
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Xylem |
transports inorganic substances (water & dissolved ions) from roots to leaves |
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Active transport |
- Goes against concentration gradient - Moves substances from area of low concentration to an area of high concentration - ENERGY NEEDED (normally ATP) |
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Pholem |
- transports organic substances produced by photosynthesis (glucose) from leaves to rest of plant |
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Facilitated diffusion |
- uses special protein transporters (channel/carrier proteins) in plasma membrane - NO ENERGY required - channel proteins: tunnel (pore) that creates hydrophilic passage, diffuses charged particles - carrier proteins: allows diffusion of 1 kind of molecule |
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Osmosis |
- movement of water from area of high water to area of low water through semi-permeable membrane |
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High water levels |
S - increased water levels R- osmoreceptors C- Hypothalamus (stops ADH release) E- Kidney tubules R- Decreased reabsorption of water, increased urine volume |
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Low water levels |
S- decrease in water level R - osmoreceptors C - Hypothalamus (1. release of ADH 2. thirst centre) E - Kidney tubules, thirst behaviour R - Increased reabsorption of water, decreased urine volume |
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Positive feedback |
Keep doing the same thing that was already happening |
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Negative feedback |
System detects change and acts to reverse change |
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Decrease of core temp |
S - Decrease in temp R - Thermoreceptors detect change C - hypothalamus E - muscles, blood vessels, body cells R - shivering, vasoconstriction, increase metabolic rate |
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Peroxisomes |
-Rich in the enzymes that detoxify various toxic materials that enter bloodstream - Responsible for oxidation of fatty acids |
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Mitochondria |
- in eukaryotic cells only - Produces adenosine triphosphate (ATP) - produces ATP through cellular respiration |
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Insulin |
- made by Beta cells - transport of glucose into some body cells - Insulin decreases glucose in blood |
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Low level of glucose |
S - decrease in blood glucose R - alpha cells of pancreas C - Alpha cells secrete glucagon E - Liver cells R - Liver cells release glycogen (glucose) |
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Glucagon |
- made by alpha cells - makes liver release stored glycogen - glucagon increases glucose in blood |
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G.A.B.I |
Glucagon released by Alpha cells Beta cells release Insulin |
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High glucose levels |
S - increased blood glucose R - beta cells in pancreas C - beta cells release insulin E - Liver cells R - uptake of glucose (by liver) |
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Respiration (continued...) |
- ADP + P = ATP - occurs in mitochondria & cytosol (95% ATP made in mitochondria) - Glucose needed for ADP to turn into ATP |
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Prokaryotic cells |
- lack membrane bound nucleus & organelles - E.G. bacteria (unicellular) - Circular DNA |
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Cell organisation |
1. Cell 2. Tissue 3. Organ 4. Organ system |
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Heterotrophs Autotrophs Chemotrophs |
Heterotrophs: obtain energy through consumption of other organisms (omnivores) Autotrophs: synthesise energy or glucose using sunlight Chemotrophs: Generate energy from inorganic substances E.G. ammonia, live in places with no light |
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Ribosomes |
- where proteins are made - Contains RNA |
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Stimulus response model |
Stimulus Receptor Control centre Effector Response |
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Homeostasis |
-maintaining a level of balance for certain physiological variables (temp, glucose, water, urea) - MAIN SYSTEM: ENDOCRINE SYSTEM |
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Biomimicry |
- practice of learning from & being inspired by nature to achieve technological advances |
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Tolerance range |
Particular environmental conditions in which an organism can survive |
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Behavioural adaptations |
Activities organism does to help survive |
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Increase of core temp |
S - hypothalamus detects increase R - thermoreceptors C - message sent to hypothalamus E - Sweat glands, blood vessels, body cells R - Sweat, vasodialate, decreased metabolic rate |
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Hypertonic Hypotonic Isotonic |
Hypertonic: having a higher solute concentration than cells content (less water outside cell) Isotonic: having equal solute concentration to that of cell Hypotonic: having a lower solute concentration than cells content (more water outside cell) |
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Eukaryotic cell |
- have membrane bound organelles E.G. animals, plants, fungi - linear DNA |
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Cell wall |
- found only in plant cells - Allows things to pass through |
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Golgi complex |
- responsible for export of substances out of cell - multi-layered structure, made of stacks of membrane line channels |
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Adaptations |
Genetically controlled feature that enhances survival |
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Structural adaptation |
Anatomical parts of the body (external) to assist survival |
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Physiological adaptation |
Internal responses made by the systems to assist survival |
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Growth rate equation |
Growth rate = (Birth + immigration) - (deaths + emigration) |
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Respiration |
- Transfer of energy from glucose to ATP glucose + oxygen -> carbon dioxide + water |
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Aerobic respiration |
oxygen needed 34 ATP's made Slow process |
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Anaerobic respiration |
no oxygen needed 2 ATP's made quick process by product of lactic acid = fatigue, muscle soreness |
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Simple diffusion |
- movement of substances from area of high concentration to area of low concentration - gases & uncharged molecules -NO ENERGY is required |
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Hypothyroidism & Hyperthyroidism |
Hypothyroidism: under-active thyroid gland that fails to secrete enough hormones Hyperthyroidism: over-active thyroid gland that produces excessive amounts of thyroxine |
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Useful forms of energy |
- ATP - Glucose - Glycogen - Starch - Fats |
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Photosynthesis |
Carbon dioxide + water -> glucose + oxygen - plants (occurs in chlorophyll found in chloroplasts) |
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Hyperthermia & hypothermia |
Hyperthermia: elevated core temp due to failure of thermoregulation Hypothermia: condition where somebody has abnormally low core temp |
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Type 1 & Type 2 diabetes |
Type 1: beta cells of the pancreas produce little to no insulin Type 2: insulin produced but the body cells do not respond (A.K.A insulin resistant) |
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Amensalism |
One organism inhibits or destroys another organism
The organism that destroys the other gains no direct benefit |
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Population distribution |
- refers to spread of members of a population over given area A - uniform B - random C - clumped |
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Commensalism |
One member gains, while nothing happens to the other (not harmed nor gains anything) |
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Cytoplasm |
- clear, thick, jelly like material - protects cell organelles |
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Mutualism |
Both organisms benefit somehow |
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Parasitism |
- Parasite lives in or on host but does not kill host - Parasite benefits (feeds off host) |
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Predator - prey relationship |
one species kills or eats another |
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breakdown of ecosystem |
Cell -> organisation -> population -> community -> ecosystem |
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Asexual reproduction |
one parental organism gives rise to 2 identical offspring EXAMPLES: binary fission (bacteria) and budding |
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Biological advantages of asexual reproduction |
- parent can produce without a mate - offspring produced at a faster rate - not a lot of energy required |
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Biological disadvantages of asexual reproduction |
- little variation in the population - rapid population growth that could lead to competition for resources - any mutation in parents DNA will be passed of to offspring |
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Clones |
asexually reproduced organisms with identical genetic makeup |
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Gametes |
cells that contain half the number of chromosomes of somatic cells |
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How are gametes formed? |
Through the process of Meiosis where genetic material is shuffled between homologous chromosomes |
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Meiosis |
process of cell division that produces daughter cells, each of which have half the number of chromosomes of the original parent cell - there a 2 nuclear divisions in meiosis |
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Prophase I |
appearance of chromosomes, crossing over between non-sister chromatids of homologous chromosomes may occur |
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Metaphase I |
Homologous chromosomes line up independently at the spindle equator |
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Anaphase I |
Homologous chromosomes separate and move towards opposite poles |
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Telophase I |
Chromosomes disappear, nuclear membrane forms and cell divides into 2 (each cell has half the number of chromosomes as the parent) |
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Prophase II |
chromosomes reappear in each cell |
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Metaphase II |
each chromosome lines up at the spindle equator |
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Anaphase II |
Centromeres are split and sister chromatids move to opposite poles |
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Telophase II |
Chromosomes disappear, the nuclear membrane reforms and each cell divides into 2 |
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Final product of meiosis |
four daughter cells variation can exist between four cells as a result from crossing over and independent assortment during meiosis 1 |
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Non-disjunction |
when chromosomes fail to separate correctly during anaphase I or anaphase II - gametes produced may have an extra copy of a chromosome or missing a chromosome |
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Biological advantages of sexual reproduction |
genetically varied offspring individual characteristics may aid in survival if environment changes |