1. Cytology, Basic Genetics and Histology (COMPLETED) Flashcards
Characteristics of life
What do we mean by differentiation?
All cells start off the same as stem cells and then change into the specialised state they will function as.
Characteristics of life
What do we mean by metabolism?
The sum of all of the chemical processes in the body through which we create energy
Characteristics of life
What do we mean by responsiveness
Ability to respond to changes in the environment
What is the difference between anatomy, physiology and pathology
Anatomy refers to the structures that form the body
Physiology refers to how those structures work. It is physiology that brings anatomy to life.
Pathology is the study of disease of abnormalities from normal function of those structures
Name FOUR characteristics of death.
o Not breathing
o Heart stopped
o No brain activity
o No Qi
Define ‘Homeostasis’.
A state of equilibrium or balance in the body’s internal environment maintained by the body’s own regulatory system.
The two regulatory systems that control this are the autonomic nervous system and the endocrine system
List FOUR physiological variables that must be maintained within homeostatic parameters.
PH levels
Body temperature
Blood pressure
Water and electrolytes
Blood glucose levels
O2 and CO2 levels in the blood and tissues
Qi
Regarding body fluids, state the name of the fluid found:
a. Inside the cell
b. Outside the cell
c. Between cells
a. Inside the cell - Intracellular , intraabdominal (withing the abdomen)
b. Outside the cell - Extracellular
c. Between cells - Interstitial (think interval between the two halves)
What are the four systems in homeostasis?
Disruptors - hot day
Detectors - Brain detects body temp is too high
Control Centre - Brain evaluates input and generates output based on this
Effectors - Sweating, dilation of blood vessels on skin, take jumper off, rest
What is the purpose of positive feedback?
Amplifies and strengthens the effector response.
For example in childbirth, the pressure on the cervix will cause the release of hormones to instruct contractions continuously until there is no pressure on the cervix when it will stop.
What is the purpose of negative feedback?
The output reverses the input.
The effector response decreases the effect of the disruptor.
For example on a hot day we might take off a jumper (output). It doesn’t change the heat of the day but it changes the body’s temperature.
Think of a heating thermostat. It is colder outside, so the heating turns up and the temperature in the room stays the same.
List TWO examples of:
a. Positive feedback
b. Negative feedback
a. Positive feedback
Childbirth, blood clotting, lactation
b. Negative feedback
Blood glucose levels low and we have something to eat, out of breath/hypoxia leading to a sit down
Name FOUR body cavities.
Cranial
Thoracic
Abdominal
Pelvic
Describe the following:
Cells
Tissues
Organs
System
Cells: The smallest living unit in the body
Tissues: Groups of cells that work together to perform a function
Organs: Groups of tissues working together to perform a specific function
System: Related organs that have a common function
Briefly explain the ‘Cell Theory’.
All known living thing are made of cells
o the cell is a structural and functional unit of all living things
o all cells come from pre-existing cells by division
o Cells all contain the same hereditary information in the form of DNA which is passed from cell to cell during cell division
o All energy flow of life (metabolism and life force) occurs within cells
Describe the relationship between cell memory and vital force/life force.
o Memories are not just stored within the brain. They are also stored within individual cells.
o Cell memory describes the ability of cells to remember experiences which influence the vital force in our cells and body.
o Traumatic experiences and even negative beliefs may be stored as a negative charge of energy in cells
o Vital force can become blocked
List THREE factors that stagnate energy in the body.
Dietary choices;
negative thoughts;
lifestyle influences;
drugs;
exposure to harmful substances such as radiaton
Name THREE heavy metals that accumulate in the body. Where might you be exposed to these?
Mercury – fish and shellfish
Lead – Paint, dust with lead
Aluminium - cooking foil, cooking pans, antiperspirants, some vaccines
Which disease is Aluminium toxicity linked to?
Alzheimers when aluminium accumulates in the brain.
Explain what is meant by ‘Oxidative Stress’.
Oxidative stress is damage caused to cells from free radicals.
Free radicals are unstable oxygen molecules that are missing an electron and in their search for a replacement electron reap damage.
Oxidative damage can occur due to stress, toxins, smoking, diets rich in refined sugars and processed foods.
How does an ‘antioxidant work’?
Name two
Antioxidants can donate the missing electron thereby mopping up free radicals.
They tend to be found in plant based foods. Quercetin, Vitamin C, E, Beta carotene
What is the term given to a cell?
a. With a nucleus
b. Without a nucleus
a. With a nucleus
Eucaryotic
b. Without a nucleus
Procaryotic
Answer the following questions comparing prokaryotic and eukaryotic cells.
Cell size:
Nucleus:
Membrane bound organelles:
Cell Wall:
Cell Division:
Example:
Cell size:
Pro - Smaller for fast reproduction
Euk - Larger
Nucleus:
Pro - No
Euk - Yes
Membrane bound organelles:
Pro - No
Euk - Yes
Cell Wall:
Pro - yes
Euk - Only in plants and Funghi
Cell Division:
Pro - Binary Fission (rapid mitosis)
Euk - Involves Mitosis for most cells meiosis for haploid cells
Example:
Pro - Bacteria; Simpler organisms
Euk- Human/ animal cell
Plants and funghi
What is the difference between cytosol and Cytoplasm
Cytosol - Basic watery fluid in the cell
Cytoplasm - Everything in the cell except between the nucleus and the membrane
Imagine it like the clear liquidy part of the egg.
Where do we find a phospholipid bilayer?
It is the plasma membrane around a cell.
- Label the diagram below indicating which section is ‘lipid’ or ‘phosphate’
Purple: The phosphate heads are the purple circles on the top and bottom. They are hydrophilic, loving water and this is great because they are in contact with water on the outside of the cell and also on the inside of the cell (cytosol)
Green: jipids. The lipid tails are green and point inwards (away from the water) as they are hydrophobic and moving away from liquid.
Explain the terms:
a. Hydrophobic
b. Hydrophilic
Every cell in the body is in contact with liquid or water on the outside but also on the inside with cytosol. Basically there is alot of water around!
a. Hydrophobic – water hating.
Eg: fats
The lipid bilayer is an example of hydrophobic where it does not like water. Think about oil in water. It does not dissolve but sits on globules
b. Hydrophilic – Water loving.
Eg: Phosphates love water
Which parts of the phospholipid bilayer are?
a. Hydrophobic
b. Hydrophilic
a. Hydrophobic
The lipid bilayer is an example of hydrophobic where it does not like water. Think about oil in water. It does not dissolve but sits on globules
b. Hydrophilic
The phospholipid bilayer is an example of this.
List THREE functions of the plasma membrane
- Transport of larger molecules such as gluccose and proteins in and out of cells through** transmembrane proteins** (aka selective doorways)
- Immunological Identity - signal to tell immune cells that it is safe and recognise our own cells. Think of it like red flags that say I am cell that belongs tho this body, please dont atack me
- Receptors for hormones sit on its surface to receive
- Cholesterol runs through the phospholipid bilayer. It supports the integrity of the membrane giving strength and reducing permeability.
State the name of a molecule with an electric charge.
Hydrogen (H+)
Ions that contain fewer electrons than protons have a net positive charge and are called cations.
Conversely, ions that contain more electrons than protons have a net negative charge and are called anions
Name ONE type of fat found in the cell membrane.
Cholesterol is found in the cell membrane and is critical for the functioning of our cells.
It gives our cells physical integrity.
It is also essential for nerve function with regard to myeline on the end of nerves.
Describe the difference between ‘tight junctions’ and ‘gap junctions’.
Cell junctions are contact and communication points between adjacent cell membranes of tightly packed cells.
Tight junctions are cells that are tightly bound together and are found in the stomach, intestines and bladder. They provide a thick barrier.Transmembrane proteins fuse cells together to reinforce junctions and seal off passageways to prevent leaking and conditions such as leaky gut.
Think like how we do woodwork
Gap Junctions are small fluid filled tunnels between neighbouring cells. For example nerves and muscles
List TWO locations where tight junctions are found.
Stomach, Intestines, bladder
Briefly explain the role of the ‘Nucleus’.
The nucleus is a spherical structure that contains the body’s genetic information in the form of DNA.
Within the nucleolus is the nucleoli which contains RNA.
The nucleus controls all of the cell’s functions and is therefore often called the brain of the cell.
Each cell contains around 6 ft of DNA. Because it is so long it has to coil around itself and creates little strands called chromatin. In a resting state this is what it looks like = spaghetti!
If that cell now wanted to reproduce the chromatin would arrange itself is very neat structures that look likes X’s. These are chromosomes.
What is the main function of the ‘Nuclear pore’?
Situated in the nuclear membrane, nuclear pores are for substance movement in and out of the nucleus
What is the cytoskeleton of the cells and list two functions
The cytoskeleton is made up of a network of protein filaments (microtubules and microfilaments), that extend and through the cytosol spreading out through the cell.
It is the scaffolding of the cell.
These protein filaments assist with
- Movement
Microtubules are major components of the cytoskeleton. Organelles use them like a tunnel to move to a different part of the cell.
Eg: Enable white blood cells to move to a site of injury; enable muscle contraction in muscle cells - Structure and shape
They are very strong and rigid and provide physical support and shape to the cell - Cell Division
They help move chromosomes apart to split them up during mitosis.
Explain the specific role of ‘Mitochondria’.
Bean shaped structures withing the cell.
The power house of the cell. It generates ATP through either aerobic or anaerobic respiration.
ATP = Adenosine triphosphate
Which body cells contain the most mitochondria?
Muscles cells needed for the energy to produce contraction. Particularly the heart which is 95% muscle.
In these muscles there can be several thousand mitochondria.
Which type of cell respiration is mainly used by mitochondria?
Aerobic which produces 38 ATP but loses 2 in the process so a net gain of 36.
What is the chemical reaction formula for aerobic respiration
Glucose* + Oxygen = Carbon dioxide + Water + Adenosine Triphosphate (ATP)
*Can use fats and proteins, in the order, but not as effective as sugar so last resort
What is the most important role of ‘Ribosomes’?
They are the smallest spherical structure you will find within the cell yet they represent 25% of the mass of the cell.
The job of ribosomes in the synthesise (produce) proteins. They receive instructions from MRNA.
They are free in the cytosol or connected to the rough endoplasmic reticulum
Explain the KEY difference between ‘mobile’ and ‘stationary’ ribosomes.
Ribosomes that are stationary and connected to the endoplasmic reticulum produce proteins that are transported out of the cell to be used elsewhere. Hormones are an example of this as they are transported to where they are needed.
Ribosomes that are free in the cytoplasm of the cells produce proteins that remain in the cell.
