Human Biology BIOL1008 questions
with correct answers rated 100%.
L201.a. Describe the main compartments of the body- inside vs outside, dorsal vs ventral, body fluids
ANS - - Inside vs Outside: features separate internal environment from the external environment e.g.
cell membrane, blood vessels, skin
- Dorsal vs Ventral: body compartments- Dorsal cavity (back- brain and spine), Ventral cavity (front-
thoracic + abdomen)
- Body fluid: 60%, water and 5-6L of blood. Intracellular fluid compartment (enclosed by cell
membranes) = 2/3 of body fluid / extra cellular fluid compartment (interstitial fluid and blood plasma) =
1/3 of body fluid
L201b. Describe the layers of organisational scale ANS - There are 6 levels of structural organisation:
- Molecular: atom and molecules interact- determines structure and function of organism
- Cellular: basic structural units
- Tissue: group of similar cells
- Organs: 2+ tissue types performing common functions
- Organ systems: group of organs performing a set of functions
- Organisms: any living things considered as a whole
L201c. (Key biological elements of the body)- Dimensionality, complexity, dynamic nature of systems,
systems operating together ANS - - Dimensionality: all is 3D
- Complexity: components are all integrated- constantly interact, work together and impact each other
- Dynamic nature of systems: body systems are able to change constantly in response to stimulus
- Systems operation together: body functioning requires systems that work together to establish
homeostasis and sustain life
L202: Explain the major themes organising the human body- scale, SA:VOL ratio ANS - - Scale: the
human body is hierarchically structured from microscopic structures to macroscopic structures
- SA:V Ratio: V affects the rate that material is made/ used in the cell, SA affects the rate that particles
can enter/ exit. Materials must be able to reach all parts of the cell quickly- if V:SA is too high, it cannot
diffuse quick enough
,- E.g. Villi- tiny cellular fingerlike projections in the intestine ^ SA without ^ V- max nutrient transfer
- E.g. Alveoli are small air sacs in the lungs- cell wall thin- min vol, max spherical SA = optimise gas
exchange
L203: Identify what is normal and abnormal in some aspects of the human body (homeostasis) ANS - -
Homeostasis is the maintenance of nearly constant conditions in the internal environment
- All organs help maintain homeostasis as its required for normal functioning despite variations
- Constituents are regulated within a range- not fixed values e.g. Calcium: 0.5-0.2 mmol/L, haemoglobin:
130-180g/L, blood ph 7.35-7.45
L301. Explain how a single cell can survive and function in isolation ANS - - The organelles in cells all
have specific functions which enables the single cell to live in isolation as long as the right nutrients and
constituents are available
- Each cell has the genetic material needed to synthesise the substances it needs
L302. Distinguish the main structure and functions of a cell an its main organelles ANS - - Cytoplasm:
jelly-like fluid. F- gives shape, contains and enables movement of materials
- Nucleus: large quantity of DNA covered by double membrane. F- control centre- sends messages,
carries genes and does RNA synthesis
- Nucleolus: non-membranous structure in the nucleus. F- production of ribosomes
- Rough ER: network of membranous sacs and tubes with ribosomes on surface. F- modify, package +
transport proteins
- Smooth ER: lipid production
- Golgi apparatus: layers of hollow curved sacs. F= protein synthesis, modification, sorting
- Lysosome: Vesicular organelles with digestive enzymes. F- breakdown materials in the cell
- Mitochondria: double membrane self-replicating structure. F- performs aerobic respiration + generates
ATP
- Cytoskeleton: network of protein filaments or tubules. F- reinforce shape, movement and transport
L303. Explain how cell membranes create compartmentalisation which regulates the flow of substances
into and out of cells ANS - - Cell membrane contains a phospholipid bilayer with proteins and other
molecules
- The phosphate are hydrophilic and lipids are hydrophobic- stops water-soluble substances
,- Membrane is impermeable to most essential ions, hydrophilic molecules e.g. glucose and large
molecules e.g. proteins
- Selectively permeable- maintains proper intracellular concentrations for functioning: not ions,
hydrophilic molecules or large substances
L304. Describe the passive diffusion of water across semipermeable cell membranes and the role of
aquaporins ANS - - Osmosis: diffusion of water across a semipermeable membrane from region of ^
water conc. to low water conc.- water can pass through cell membrane due to differences in osmotic
pressure (tendency for water to move into a solution e.g. low water conc sol= hypotonic)
- Aquaporins are integral membrane proteins that act as channels for the transfer of water- important
for rapid transport e.g. intestines as water cannot easily move across membrane
L305. Describe how the cell uses the Na-K ATPase to create the electrochemical gradient that provides
the energy for life ANS - - The sodium-potassium pump uses the Na+-K+ ATPase enzyme to actively
transport sodium ions out of cells and potassium ions into cells
- 2 K+ bind on outside, 3 Na+ bind on inside
- ATPase breaks down ATP which releases ions through to either side (Na out)
- Results in negative charge on the inside- creates electrochemical gradient (Na ions drawn into cell due
to conc. and charge) which is used as driving force for other molecules to do facilitated diffusion
L306. Explain how larger molecules and particles get in and out of cells ANS - - Large substances move
through active transport using vesicles
- Endocytosis: uptake of material through cell membrane by formation of a vesicle
- Receptor-mediated endocytosis: specific receptor molecules on membrane bind to specific substances
which triggers endocytosis
- Phagocytosis: part of cell membrane extends around particle and fuses so it's surrounded
- Exocytosis: membrane-bound sacs containing materials fuse with cell membrane and releases outside
L401: Outline the major uses of energy in humans
L402: Describe the role of ATP as the common intracellular energy source for human cells ANS - - ATP is
a high-energy molecule that stores energy to be used by the cell
- The last phosphate bond has high stored energy which is released when broken
, - ATP has 3 main roles: active transport of substances through the cell membrane e.g. ions, synthesis of
chemical compounds e.g. protein synthesis and mechanical work- muscle contractions and internal
movement of substances and pumping of the heart
L403. Compare and contrast the role of glucose and fatty acids as substrates for ATP production ANS - -
D: Glucose is converted to pyruvic acid through glycolysis which is the only anaerobic process of ATP
production- fatty acids can only be used when O2 is present
- S: Pyruvic acid as well as fatty acids are converted to Acetyl-CoA groups to be used to generate a lot of
ATP
L404. Distinguish between aerobic and anaerobic metabolism as mechanisms to product ATP from
glucose and fatty acids ANS - - Aerobic metabolism: presence of O2, occur in cytoplasm or
mitochondria, produces CO2 and H2O from combustion of fuels
- Anaerobic: without O2, less ATP (2 vs 38), only in cytoplasm (glycolysis), produces lactic acid
L405: Describe the differences in preferences for metabolic substrates between skeletal muscle, heart
muscle and brain and the implications for these in starvation ANS - - Brain: glucose
- Skeletal muscle: Fatty acids, glucose
- Heart muscle: fatty acids, lactate
- Implications on starvation- 4 hours after a meal, glucose usage reduces other than brain, after 30h- all
except brain stop using glucose
- Ketone bodies are produces in liver during starvation which can be used for energy
- The body can synthesise its own glucose using proteins and lactate during starvation
L501. Explain why blood flows continuously around the body ANS - - The circulatory system enables
blood to flow continuously through a closed circulatory system and a double circulatory system
- 1 reason: ensures oxygen, nutrients, water and other are delivered to cells- enabling ATP production
and survival
- 2 reason: transport hormones, white blood cells and antibodies
- 3 reason: collect carbon dioxide and metabolic wastes and transport them for excretion
L502: List the key differences between the three main types of blood vessels ANS - Function: A- carry
blood away from heart/ V- return blood to heart/ C- facilitate diffusion
with correct answers rated 100%.
L201.a. Describe the main compartments of the body- inside vs outside, dorsal vs ventral, body fluids
ANS - - Inside vs Outside: features separate internal environment from the external environment e.g.
cell membrane, blood vessels, skin
- Dorsal vs Ventral: body compartments- Dorsal cavity (back- brain and spine), Ventral cavity (front-
thoracic + abdomen)
- Body fluid: 60%, water and 5-6L of blood. Intracellular fluid compartment (enclosed by cell
membranes) = 2/3 of body fluid / extra cellular fluid compartment (interstitial fluid and blood plasma) =
1/3 of body fluid
L201b. Describe the layers of organisational scale ANS - There are 6 levels of structural organisation:
- Molecular: atom and molecules interact- determines structure and function of organism
- Cellular: basic structural units
- Tissue: group of similar cells
- Organs: 2+ tissue types performing common functions
- Organ systems: group of organs performing a set of functions
- Organisms: any living things considered as a whole
L201c. (Key biological elements of the body)- Dimensionality, complexity, dynamic nature of systems,
systems operating together ANS - - Dimensionality: all is 3D
- Complexity: components are all integrated- constantly interact, work together and impact each other
- Dynamic nature of systems: body systems are able to change constantly in response to stimulus
- Systems operation together: body functioning requires systems that work together to establish
homeostasis and sustain life
L202: Explain the major themes organising the human body- scale, SA:VOL ratio ANS - - Scale: the
human body is hierarchically structured from microscopic structures to macroscopic structures
- SA:V Ratio: V affects the rate that material is made/ used in the cell, SA affects the rate that particles
can enter/ exit. Materials must be able to reach all parts of the cell quickly- if V:SA is too high, it cannot
diffuse quick enough
,- E.g. Villi- tiny cellular fingerlike projections in the intestine ^ SA without ^ V- max nutrient transfer
- E.g. Alveoli are small air sacs in the lungs- cell wall thin- min vol, max spherical SA = optimise gas
exchange
L203: Identify what is normal and abnormal in some aspects of the human body (homeostasis) ANS - -
Homeostasis is the maintenance of nearly constant conditions in the internal environment
- All organs help maintain homeostasis as its required for normal functioning despite variations
- Constituents are regulated within a range- not fixed values e.g. Calcium: 0.5-0.2 mmol/L, haemoglobin:
130-180g/L, blood ph 7.35-7.45
L301. Explain how a single cell can survive and function in isolation ANS - - The organelles in cells all
have specific functions which enables the single cell to live in isolation as long as the right nutrients and
constituents are available
- Each cell has the genetic material needed to synthesise the substances it needs
L302. Distinguish the main structure and functions of a cell an its main organelles ANS - - Cytoplasm:
jelly-like fluid. F- gives shape, contains and enables movement of materials
- Nucleus: large quantity of DNA covered by double membrane. F- control centre- sends messages,
carries genes and does RNA synthesis
- Nucleolus: non-membranous structure in the nucleus. F- production of ribosomes
- Rough ER: network of membranous sacs and tubes with ribosomes on surface. F- modify, package +
transport proteins
- Smooth ER: lipid production
- Golgi apparatus: layers of hollow curved sacs. F= protein synthesis, modification, sorting
- Lysosome: Vesicular organelles with digestive enzymes. F- breakdown materials in the cell
- Mitochondria: double membrane self-replicating structure. F- performs aerobic respiration + generates
ATP
- Cytoskeleton: network of protein filaments or tubules. F- reinforce shape, movement and transport
L303. Explain how cell membranes create compartmentalisation which regulates the flow of substances
into and out of cells ANS - - Cell membrane contains a phospholipid bilayer with proteins and other
molecules
- The phosphate are hydrophilic and lipids are hydrophobic- stops water-soluble substances
,- Membrane is impermeable to most essential ions, hydrophilic molecules e.g. glucose and large
molecules e.g. proteins
- Selectively permeable- maintains proper intracellular concentrations for functioning: not ions,
hydrophilic molecules or large substances
L304. Describe the passive diffusion of water across semipermeable cell membranes and the role of
aquaporins ANS - - Osmosis: diffusion of water across a semipermeable membrane from region of ^
water conc. to low water conc.- water can pass through cell membrane due to differences in osmotic
pressure (tendency for water to move into a solution e.g. low water conc sol= hypotonic)
- Aquaporins are integral membrane proteins that act as channels for the transfer of water- important
for rapid transport e.g. intestines as water cannot easily move across membrane
L305. Describe how the cell uses the Na-K ATPase to create the electrochemical gradient that provides
the energy for life ANS - - The sodium-potassium pump uses the Na+-K+ ATPase enzyme to actively
transport sodium ions out of cells and potassium ions into cells
- 2 K+ bind on outside, 3 Na+ bind on inside
- ATPase breaks down ATP which releases ions through to either side (Na out)
- Results in negative charge on the inside- creates electrochemical gradient (Na ions drawn into cell due
to conc. and charge) which is used as driving force for other molecules to do facilitated diffusion
L306. Explain how larger molecules and particles get in and out of cells ANS - - Large substances move
through active transport using vesicles
- Endocytosis: uptake of material through cell membrane by formation of a vesicle
- Receptor-mediated endocytosis: specific receptor molecules on membrane bind to specific substances
which triggers endocytosis
- Phagocytosis: part of cell membrane extends around particle and fuses so it's surrounded
- Exocytosis: membrane-bound sacs containing materials fuse with cell membrane and releases outside
L401: Outline the major uses of energy in humans
L402: Describe the role of ATP as the common intracellular energy source for human cells ANS - - ATP is
a high-energy molecule that stores energy to be used by the cell
- The last phosphate bond has high stored energy which is released when broken
, - ATP has 3 main roles: active transport of substances through the cell membrane e.g. ions, synthesis of
chemical compounds e.g. protein synthesis and mechanical work- muscle contractions and internal
movement of substances and pumping of the heart
L403. Compare and contrast the role of glucose and fatty acids as substrates for ATP production ANS - -
D: Glucose is converted to pyruvic acid through glycolysis which is the only anaerobic process of ATP
production- fatty acids can only be used when O2 is present
- S: Pyruvic acid as well as fatty acids are converted to Acetyl-CoA groups to be used to generate a lot of
ATP
L404. Distinguish between aerobic and anaerobic metabolism as mechanisms to product ATP from
glucose and fatty acids ANS - - Aerobic metabolism: presence of O2, occur in cytoplasm or
mitochondria, produces CO2 and H2O from combustion of fuels
- Anaerobic: without O2, less ATP (2 vs 38), only in cytoplasm (glycolysis), produces lactic acid
L405: Describe the differences in preferences for metabolic substrates between skeletal muscle, heart
muscle and brain and the implications for these in starvation ANS - - Brain: glucose
- Skeletal muscle: Fatty acids, glucose
- Heart muscle: fatty acids, lactate
- Implications on starvation- 4 hours after a meal, glucose usage reduces other than brain, after 30h- all
except brain stop using glucose
- Ketone bodies are produces in liver during starvation which can be used for energy
- The body can synthesise its own glucose using proteins and lactate during starvation
L501. Explain why blood flows continuously around the body ANS - - The circulatory system enables
blood to flow continuously through a closed circulatory system and a double circulatory system
- 1 reason: ensures oxygen, nutrients, water and other are delivered to cells- enabling ATP production
and survival
- 2 reason: transport hormones, white blood cells and antibodies
- 3 reason: collect carbon dioxide and metabolic wastes and transport them for excretion
L502: List the key differences between the three main types of blood vessels ANS - Function: A- carry
blood away from heart/ V- return blood to heart/ C- facilitate diffusion
