Cell Injury

Question 1

Function of Rough and smooth endoplasmic reticulum:

Answer 1

produce proteins for the rest of the cell to function, the rough contains ribosomes

Question 2

Function of mitochondria:

Answer 2

generate chemical energy to power the cells biochemical reactions.

Question 3

function of golgi apparatus

Answer 3

transport, sort, modifies proteins and lipids

Question 4

function of ribosomes

Answer 4

site of protein synthesis

Question 5

function of lysosomes

Answer 5

digestive system of the cell. breakdown macromolecules, respond against foreign substances such as bacteria, viruses etc

Question 6

function of centrioles

Answer 6

organise microtubules that serve as cells skeletal system. helps determine location of nucleus and other organelles

Question 7

function of nucleolus

Answer 7

produce and assemble cells ribosomes. where ribosomal RNA genes are transcribed

Question 8

building the body:

Answer 8

atoms, molecules, cells, tissues, organs, organ system

Question 9

what is cell injury and disease?

Answer 9

disease is any departure from normal state of health

Question 10

what are symptoms?

Answer 10

diseases present with problems such as pain

Question 11

what are signs?

Answer 11

abnormalities noticed by physician e.g. abnormal heart rate

Question 12

what is diagnosis?

Answer 12

finding nature of disease

Question 13

what is prognosis?

Answer 13

predicting future course of disease

Question 14

what are the three types of cell injury explained?

Answer 14

Acquired - developed after birth due to environmental or external factors

genetics - happening in families, abnormality in base sequence of DNA

congenital - present from birth, developed during foetal life

Question 15

what is Ischaemia? with example

Answer 15

lack of blood flow through tissue, leads to hypoxia anoxia
disrupts oxidative metabolism and leads to cell injury or death.
e.g. ischaemic stroke - oxygen rich blood flowing to the brain is restricted by blood clot or blockage
Heart attack - happens if cardiac ischaemia occurs to long, heart tissue dies then myocardial infraction

Question 16

what is hypoxia and anoxia?

Answer 16

hypoxia is when oxygen isn’t available to maintain homeostasis
anoxia is the complete loss of oxygen

Question 17

what are the 7 causes of cell injury?

Answer 17

physical agents
chemical agents
infectious agents
nutritional disorders
immunological disorders
genetic disorders
congenital

Question 18

what are physical agents?

Answer 18

• excessive heat/cold
  low temps induces vasoconstriction and impairment of blood supply
  heat applies locally causing burns
• radiation - may damage tissues e.g. sun burn or x ray burns
• trauma - resulting in wounds, bruises, fractures, dislocation
• electric current - sudden death by electric current of high voltage

Question 19

what are chemical agents?

Answer 19

A compound can react directly with some molecular components of the cell interfering with function

e.g.
chronic exposure to ethyl alcohol causing cirrhotic liver
the replacement of liver tissues by fibrosis scar tissue tissue as well as regenerative nodules

Question 20

what are infectious agents?

Answer 20

species of viruses, bacteria, protozoa and fungi are able to invade and multiply within hosts and cause diseases.

Question 21

what are nutritional disorders?

Answer 21

over nutrition - causing obesity, linked to disease such as cardiovascular disease
under nutrition - deficiencies e.g vitamin D, prevents bone development.

Question 22

what are immunological disorders?

Answer 22

the immune system protects humans but in certain circumstances reactions damage tissues
causing e.g autoimmune disease, hypersensitivity reactions .

Question 23

what are genetic disorders?

Answer 23

some abnormalities in the base sequence in DNA of the fertilised ovum and cell derived from it.

e.g sickle cell - life long blood disorder
red blood cells that have abnormal rigid sickle shape.
sickling decreases cells flexibility resulting in complications
occurs because of mutation in haemoglobin.

Question 24

what is congenital disorders?

Answer 24

disease was present at birth.
caused by defect in the cellular process of development.
e.g cerebellar hypoplasia
in calves where the cerebullum fails to develop due to transmission of virus of mucosal disease from mother to foetus during pregnancy

Question 25

what are cells divided into? (3 ways)

Answer 25

• cells that divide and replicate continuously
• cells that don’t normally replicate continuously, but are capable of cell division
• cells that are incapable of cell division

Question 26

what is cellular adaptation?

Answer 26

non lethal/reversible injury

Question 27

what is cell death?

Answer 27

lethal/irreversible injury

Question 28

what are the three reactions to cell injury?

Answer 28

• increased cellular injury: hypertrophy, hyperplasia
• decreased cellular activity: atrophy
• change in cell type or position: metaplasia or dysplasia

Question 29

what is hypertrophy?

Answer 29

increase in size of cell which results in enlargement seen in cells that can’t divide e.g skeletal muscle and cardiac muscle.

Question 30

what is hyperplasia?

Answer 30

an increase in the number of cells. seen in cells that are capable of mitotic division
hyperplasia can be classified of:
- physiologic: hormonal
- compensatory: regeneration of liver following partial hepactomy
- pathologic; excessive hormal stimulation

Question 31

what is atrophy?

Answer 31

a decrease in size by loss of cellular substance or number of cells
classified as:
physiologic: due to decreased workload
pathologic: decreased workload, decreased blood supply, nutritional deficiency

Question 32

what is metaplasia?

Answer 32

change in cell type or position
original cells are replaced by cells that are better suited to tolerate abnormal environment.