Week 1 Introduction and Homeostasis ✅

Question 1

What is homeostasis?

Answer 1

The state of a constant internal environment

Question 2

What factors contribute to homeostasis?

Answer 2

Osmolarity, pH, O2 and temperature

Question 3

What is the role of rough endoplasmic reticulum?

Answer 3

Process proteins

Question 4

What is the role of soft endoplasmic reticulum?

Answer 4

Process lipids

Question 5

What is the role of centrioles?

Answer 5

Cell division

Question 6

What is the role of lysozomes?

Answer 6

Digestion

Question 7

What is the role of golgi?

Answer 7

Packaging

Question 8

What is the significance of hypertonic and hypotonic fluid with cells?

Answer 8

Fluid outside cells is hypertonic
Fluid inside cells is hypotonic

Question 9

What is potassium involved in?

Answer 9

Cardiac contraction

Question 10

Where are goblet cells located?

Answer 10

Intestines and lungs

Question 11

What are the precursor of osteocytes?

Answer 11

Osteoblasts

Question 12

What are blast cells?

Answer 12

Early cells

Question 13

Why does a sperm cell have mitochondria in its head?

Answer 13

Movement

Question 14

What is a totipotent cell?

Answer 14

Can form any cell

Question 15

What is a pluripotent cell?

Answer 15

Can form >200 cell types

Question 16

What is a multipotent cell?

Answer 16

A differentiated cell but can form multiple

Question 17

What is a unipotent cell?

Answer 17

Can only form 1 cell type

Question 18

What triggers DNA (genes) to make certain proteins?

Answer 18

Transcription factors/regulatory proteins

Question 19

What are the features of a stem cell?

Answer 19

Self renew and differentiate into any cell

Question 20

What does apoptosis mean?

Answer 20

Cell death

Question 21

What is the role of cholesterol?

Answer 21

Regulate communication
Keep cell membranes fluid

Question 22

What is endocytosis?

Answer 22

Engulf and bring into cell as a vesicle and recycle into cell membrane

Question 23

What kinds of molecules can cross cell layers easily and what examples?

Answer 23

Non-polar molecules e.g. O2, CO2, vitamins

Question 24

What is the purpose of trans-membrane protein channels?

Answer 24

To transport charged/polar molecules

Question 25

Which part of the bilayer is hydrophilic and which is hydrophobic?

Answer 25

Hydrophilic (charged) head Hydrophobic tail (Tails are pointed together)

Question 26

Are hormones and blood pressure under homeostatic control?

Answer 26

Yes

Question 27

Is heart rate and body fat under homeostatic control?

Answer 27

No

Question 28

Are blood gas levels under homeostatic control?

Answer 28

Yes

Question 29

What are the features of negative feedback loop?

Answer 29

Stimulus → receptors → control centre → effectors

Question 30

What does a baroreceptor measure?

Answer 30

Blood pressure

Question 31

What does a chemoreceptor measure?

Answer 31

Blood gases

Question 32

What does a thermoreceptor measure?

Answer 32

Temperature of the skin and organs

Question 33

What does an osmoreceptor measure?

Answer 33

Osmolarity

Question 34

What does a glucoreceptor measure?

Answer 34

Glucose

Question 35

Give an example of a positive feedback situation

Answer 35

Childbirth - Oxytocin

Question 36

What is the difference between positive and negative feedback?

Answer 36

Positive feedback moves the changes further away until it reaches an END POINT

Question 37

When would the body temperature 'set point' be altered?

Answer 37

Fever

Question 38

What effect does a high temperature have on the body?

Answer 38

Stimulate WBC production and activity

Question 39

Why is the elderly and infants more susceptible to problems with heat?

Answer 39

The elderly's hearts are not as efficient in helping to regulate temperature Infants have a high surface area:volume so lose heat more easily

Question 40

How do we get temperature 'in'?

Answer 40

Radiant heat Voluntary production of heat e.g. muscles Involuntary production of heat e.g. shivering

Question 41

How do we get temperature 'out'?

Answer 41

Evaporation of sweat Conduction, convection

Question 42

Which part of the brain is involved in temperature regulation?

Answer 42

Hypothalamus

Question 43

What is an 'anticipatory' response?

Answer 43

Sympathetic response e.g. white coat syndrome with BP, about to run a race - heart racing before even set off

Question 44

What is sensitisation?

Answer 44

Where there is more than 1 stimulus e.g. O2 and CO2 both affecting

Question 45

What is 'feed forward' and what is an example?

Answer 45

Similar to anticipation response but at a lower threshold E.g. having a drink and stopping before osmoreceptors detect plasma osmolarity return

Question 46

How does behaviour affect homeostasis?

Answer 46

Babies and infants may not be able to do certain tasks The elderly may forget to do certain tasks

Question 47

How does 'accomodation' affect homeostasis?

Answer 47

Changes cell sensitivity

Question 48

How does 'acclimation' affect homeostasis?

Answer 48

Long term adaptations - artificial means (lab)

Question 49

How does 'acclimatisation' affect homeostasis?

Answer 49

Long term adaptations - natural means

Question 50

How does 'genetic adaptation' affect homeostasis?

Answer 50

'Survival of fittest'

Question 51

How does 'inherited adaptation' affect homeostasis?

Answer 51

Years of generations e.g. fat, cold environment

Question 52

How does 'acquired adaptation' affect homeostasis?

Answer 52

1) Mins/hours - cold, pH etc 2) Days/weeks - sweat