Life Processes Flashcards
What are the 6 levels of organisation in the body?
- Organism level
- Organ system level
- Organ level
- Tissue level
- Cellular level
- Chemical level
What are organs made of?
Multiple types of tissues
Example: skin
What are the 4 basic tissues?
Epithelial - lines surfaces
Connective - structural support
Muscle tissue - contracts
Nervous tissue - conducts electricity
What are tissues made of?
Each type of tissue is made up of cells which determines the function
What are cells?
The smallest living units that carry out all vital physiological functions
What is an element?
A pure substance. Can exist as a single atom or molecule made of the same type of atom
What is an atom?
The smallest particle of an element
What are molecules?
Made of two or more atoms either:
- Of the same element eg. 2 hydrogen OR
- As a compound eg. 2 hydrogen + 1 oxygen
What are the 4 most common elements in the body?
- Oxygen (65%)
- Carbon (18%)
- Hydrogen (10%)
- Nitrogen (3%)
What percentage of solids are in the body?
40-45%
What percentage of fluids is in the body?
55-60%
What is the total body water (TBW)?
All water within and outside of all the cells of the body
What percentage of the TBW is intracellular fluid (ICF)?
66% (2/3)
What percentage of the TBW is extracellular fluid (ECF)
33% (1/3)
What are the two divisions of ECF?
80% interstitial fluid
20% blood plasma
Do bodies with more fat have lower or higher TBW?
Bodies with more fat have lower TBW (~55% or less)
Bodies with more muscle have higher TBW (~60%)
What are atoms composed of?
Protons, Neutrons and Electrons
How many electrons can the inner shell of an atom hold?
Max 2
How many electrons can the outer shell of an atom hold?
max 8
What is a reactive atom?
When the outer shell isn’t full
What is a cation?
A positively charged ion.
The atom needs to give away an electron to become stable. Therefore it loses an electron, making it more positive.
What is an anion?
A negatively charged ion.
The atom needs to receive an electron to become stable. There it gains an electron and becomes more negative.
What is an Ionic Bond?
Electron Exchange. An electrostatic attraction between two atoms where one atom gives an electron to the other. Eg. NaCl
What is a covalent bond?
Electron Sharing. Eg. A water molecule is created when 2 hydrogen atoms and 1 oxygen atom share electrons.
Which bond is weaker; ionic or covalent?
Ionic bonds are weaker than covalent bonds
Why do things dissolve in water?
Because water molecules are polar (one side is positive and the other is negative). Therefore they break the solutes ionic bonds.
Why doesn’t oil dissolve in water?
Because they are non-polar. Only polar molecules can dissolve in a polar solvent.
What is an electrolyte?
“loosened electricity.” Any molecule that creates an electrically conducting solution when dissolved in water.
What are 4 examples of electrolytes?
- NaCl (sodium chloride) –> Na + Cl
- KCl (potassium chloride) –> K + Cl
- CaPO4 (calcium phosphate) –> Ca + PO4
- NaHCO3 (sodium bicarbonate) –> Na + HCO3
What do carbs get broken down to?
Glucose and other monosaccharides
What do lipids get broken down to?
Fatty acids and glycerol
What do proteins get broken down to?
Amino acids and polypeptides
What do we use macromolecules for? (4)
- Build cellular structures
- Repair cellular structures
- Build products for export
- Create ATP
How do cells make ATP?
Through cellular respiration that occurs in the mitochondria
What is the ATP-CP system?
- Anaerobic (no oxygen used)
- 1 molecule of creatine phosphate makes 1 ATP
- Explosive exercise (1-15seconds)
What is the Glycolytic System?
- Anaerobic
- 1 molecule of glucose makes 2-3-ATP
- Short-term high intensity exercise (10s - 3mins)
What is the Oxidative System?
- Aerobic
- 1 molecule of glucose makes 36-39 ATP
- 1 fatty acid molecule makes ~100ATP
- Long-term low intensity exercise (3min - hours)
What is an Organelle?
A structure within a cell that has a specific function
What is the plasma membrane?
A semi-permeable membrane, allowing certain substances in or out. The tail is hydrophobic (hates water) and the head is hydrophilic (loves water)
Why do cells have receptors?
For specific chemical messages (neurotransmitters and hormones)
What does cilia do?
Beat to move substances. eg. move mucus up the airways so you can cough it out
What does microvilli do?
Increases surface area. eg. absorptive cells that line your gut wall
What does flagella do?
Help single cells to move. eg. sperm
What is the cytoplasm and what is it made of?
The fluid part of the cell, made of:
- Water
- Ions
- Molecules for making ATP
- Molecules for building cell structures
What is the cytoskeleton?
A network of interlinking protein strands:
- connecting organelles in the cell
- forms the shape of the cell
- transport highway within the cell
What is the nucleus?
The ‘controller’ of the cell, store’s the cell’s DNA
What is the nucleolus?
The part of the nucleus that creates ribosomes
What is the endoplasmic reticulum?
The ‘construction warehouse.’ Made of a phospholipid bilayer.
What does the smooth ER build?
Lipids
What does the rough ER build?
Proteins
What is the process that happens in the Endoplasmic Reticulum? (5)
- Ribosomes convert genetic code into amino acids
- As amino acids are linked together they form proteins
- Proteins are transported in vesicles
- Vesicles are created as a bit of ER membrane pinches off
- Vesicles transport proteins to the golgi apparatus
What is the golgi apparatus?
The ‘gift wrapping, post office.’
- Protein process and packaging
- breaks large proteins into smaller ones
- can add carbohydrates to the proteins
- repackage products into vesicles to transport out of the cell
What is the Mitochondria?
The ‘powerhouse’ of the cell. Use fuel molecules and oxygen to create ATP through cellular respiration
What is diffusion?
The movement of particles from areas of high concentration to low concentration, down a gradient
What is osmosis?
The diffusion of water across a semi-permeable membrane
What is osmolarity?
The concentration of solutes in a solution. Measured in mosmol/L. Water moves towards an area of high osmolarity
What is a hyper-osmotic ECF solution?
Having a higher concentration of solutes, so less water. Water moves out which makes cells shrink
What is a hypo-osmotic ECF solution?
Having less solutes, so more water. Water moves in which makes cells swell
How do electrolytes, water and macromolecules get into the cells?
By passive and active transport
What requires channels to cross the membrane?
Ions and large polar molecules
What can diffuse directly across a membrane, without channels?
Gases, water and fats/lipids
What is a concentration/chemical gradient?
When the concentration of particles is higher in one area and lower in another
What is an electrical gradient?
When charged particles move towards an area with opposite charge.
What is endocytosis?
The plasma membrane deforms to engulf (swallow) a substance and pull it in
What is exocytosis?
The plasma membrane deforms to release a substance into the ECF
What is the electrochemical gradient?
Na+/K+-ATPase pumps are constantly pumping 3Na out and 2 K in. Makes it more negative inside the cell (electrical gradient) and makes Na+ more abundant outside and K+ inside (chemical gradient)
What is primary active transport?
Uses ATP to move substances against a gradient
What is secondary active transport?
Substances move down gradients created by primary active transport pumps, forcing other substances to move with them.
Whats the Na+/glucose co-transporter?
Na+/K+ ATPase pump creates a gradient that favours sodiums entry into the cell, a Na+/glucose co-transporter uses that to move glucose into the cell. Na+ moves down its gradient, forcing glucose against its own concentration gradient
What is a pressure gradient?
The difference in pressure between two points in a system
Where is blood made?
In the bone marrow
What is blood made of?
- Hematocrit: red blood cells
- Buffy coat: white blood cells, platelets
- Plasma: water, proteins, nutrients, hormones etc.
What are the three main cells in the blood?
- Red blood cells (99.9%)
- White blood cells (<0.1%)
- Platelets (<0.1%)
Ratio of fluids to solids in the blood?
55% fluid (plasma)
45% solid (cells)
What is blood plasma made of?
- Water (92%)
- Plasma proteins (7%)
- Other solutes (1%)
What are the 5 main functions of blood?
- Maintaining core body temperature
- Transporting substances around the body
- Maintaining ion and nutrient balance
- Injury repair
- Immunity
What is the normal core body temperature?
Set-point 37degrees (36.5-37.5)
Blood holds heat very well
What is the most common plasma protein?
Albumin (50-60% of all protein in the plasma)
What does albumin do?
Transports hormones, essential lipids, minerals and other nutrients. Creates an osmotic force to keep water in the blood to maintain blood volume.
What is haemoglobin?
Important protein found in the red blood cells.
Transports oxygen from lungs to cells.
Transports carbon dioxide from cells to lungs
What is fibrinogen?
A plasma protein that creates a mesh at the wound to stop bleeding
What is globulin?
A plasma protein that helps enhance blood clotting processes. Forms antibodies that immobilise pathogens
What are platelets?
Small flat blood cells that form a plug at the wound to stop bleeding
What are erythrocytes?
Red blood cells, get caught in the fibrin mesh to stop bleeding
What are leukocytes?
White Blood Cells
- help recognise a foreign substance
- release antibodies
- release inflammatory chemicals
- kill bacteria and other pathogens
What is homeostasis?
The body processes involved in maintaining a balanced internal environment
What are examples of causes of imbalance in the body? (5)
Growth, reproduction, exercise, stress and illness
What is feedfoward feedback?
Preparation before a regulated variable changes. Anticipation/prevention of change
What is negative feedback?
Correction of changes to the regulated variable
What are the parts of a negative feedback loop?
Stimulus
Sensor
Control Centre
Effector
What is blood glucose and its range?
Blood glucose is the primary fuel to make ATP
Normal blood glucose range is 4-6mmol/L (if fasting)
What is blood pH and its range?
pH is the measure of acidity (the concentration of H+ in the blood)
Normal range is 7.35-7.45
What happens to Blood pH during exercise?
More lactic acid, CO2 and H+ produced which increases acidity, meaning decreased pH
What is hyperthermia?
When the body temp is too hot, leads to protein damage
What is hypothermia?
When the body temp is too cold, leads to slower physiological processes
What is ECF osmolarity and its range?
The concentration of solutes in the extracellular fluid.
Normal ECF osmolarity is about 300mosmol/L
What happens if there is increased ECF osmolarity (eg. dehydration)?
More water is loss, so higher solute concentration. Water moves out of cells causing them to shrink. = reduced exercise performance
What happens if there is decreased ECF osmolarity (eg. overhydration)?
Too much water ingested, so lower solute concentration. Water moves into cells causing them to swell or burst. = reduced exercise performance
What is the normal range for blood pressure?
From 90/60mmHg to 130/85mmHg
What is Mean Arterial Blood Pressure (MABP) and its range?
The average blood pressure within all the arteries. Normal operating range is 70-100mmHg. Needs to be high enough to control flow into tissues
