Muscular

Question 1

Muscles constitute what percentage of body mass?

Answer 1

40-50%

Question 2

Anatomical into of muscles

Answer 2

Myofibrils

Question 3

Functional unit of muscles

Answer 3

Sarcomere

Question 4

Are muscle cells excitable?

Answer 4

Some, yes. Eg: heart cells (AV nodes, SN nodes, Purkinje)

Question 5

Define HYPERPLASIA

Answer 5

Increase in cell number

Question 6

Define HYPERTROPHY

Answer 6

Increase in cell size

Question 7

Define ATROPHY

Answer 7

Malnourished

Question 8

Give substance to the following terms with respect to muscular tissue:
Hyperplasia
Hypertrophy
Atrophy

Answer 8

Hyperplasia is not seen in muscles

Hypertrophy is seen in muscles (gym- body building)

Atrophy (PEM eg Kwashiorkar, Marasmus)

Question 9

Why are certain muscles striated?

Answer 9

All muscles contain contractile actin and myosin proteins . In some muscles these proteins are arranged in an orderly manner (eg skeletal, cardiac) while in others (eg smooth) they ARE PRESENT, just not arranged in an orderly manner.

Question 10

Do smooth muscles have troponin?

Answer 10

No, they have CALMODULIN

Question 11

Cardiac muscles are multinucleate. Comment.

Answer 11

FALSE. Uninucleate.

Question 12

Skeletal muscles are branched/Unbranched.

Answer 12

UNBRANCHED Skeletal muscles.

Question 13

Which tissue out of the three classifications, is FUNCTIONALLY SYNCITIAL

Answer 13

Cardiac

Question 14

Smooth muscles show fast/slow contractions.

Answer 14

Sloooooow

Question 15

Smooth muscles are thickly wrapped with sarcolemma

Answer 15

FALSE

Question 16

With respect to the outer connective sheath (epi-, Peri-, endo-) which ones are present in Cardiac

Answer 16

Endomysium

Question 17

Out of the three connective sheaths which wrap muscles, which is absent in smooth muscles

Answer 17

Epimysium.

Smooth muscles have ENDOMYSIUM AND PERIMYSIUM

Question 18

Skeletal muscles have which three connective sheaths which cover it

Answer 18

EPIMYSIUM, PERIMYSIUM, ENDOMYSIUM

Question 19

Define fascia, fascicle

Answer 19

One tube (fibre?) + ENDOMYSIUM = Unit A

Many units of A group together + PERIMYSIUM= Fascicle

Many fascicles come together and get covered by EPIMYSIUM to form fascia

Question 20

Why do red muscle cells have SLOW contractions (why white ones have fast muscle contractions)

Answer 20

Because red muscles cells may be having higher count of mitochrmondria which supplements their higher rate of contractions, but they have LESS SARCOPLASMIC RETICULUM, hence a bit short on the calcium reserves which is seen in their slower contractions.

Question 21

Can muscle development be altered by training?

Answer 21

Yes, however HYPERPLASIA is never seen in muscle cells, HYPERTROPHY is. And accordingly, specific, customized training can shape the body in the a particular way.
Eg. Marathon runners and sprinters have different prominent skeletal muscle types. Former will have more developed red muscle fibres while the sprinters will have more white muscle fibres.

Question 22

Classification of smooth muscles based on gap junction.

Answer 22

Single unit (bladder) and multi unit muscles (iris, erector pili, large blood vessels)

Question 23

Where all do we find gap junctions (name three examples)

Answer 23

Epithelial
Cardiac
Single unit smooth muscles

Question 24

Brain tumour term

Answer 24

Glioma

Question 25

Which neuron is in direct contact with the external environment

Answer 25

Olfactory neuron

Question 26

Which neurons can divide

Answer 26

Olfactory neurons (in direct contact with the environment hence have to be replaced) and astrocytes (repair and form other cells)

Question 27

Term perikaryon refers to

Answer 27

Cyton/Soma i.e. cell body of a neuron

Question 28

Node to node conduction is aka

Answer 28

Saltatory conduction

Question 29

One Schwann cell wraps around one/many axons?

Answer 29

ONE axon (monogamous)

Question 30

Schwann cells are absent in non medullated neurons

Answer 30

False. They just don’t secrete the myelin sheath

Question 31

Neurilemma is continuous/discontinuous?

Answer 31

CONTINUOUS.

Question 32

Neurilemma is absent in?

Answer 32

C N S

Since Schwann cells are absent in CNS

Question 33

Oligodendrocytes are present in?

Answer 33

CNS

Question 34

Name two neuroglial cells which are responsible for myelin sheath formation

Answer 34

Oligodendrocytes (CNS, no neurilemma, wraps around many axons)
Schwann cells (PNS, neurilemma, wraps around only one axon)

Question 35

Neurons of which nervous system are completely non reparable

Answer 35

Central nervous system

Question 36

How do oligodendrocytes wrap around the axons of neurons?

Answer 36

They have cytoplasmic processes.

Question 37

Grey matter? White matter? Say whaaaaaat?

Answer 37

Myelin sheath gives white colour.

Brain: outer grey and inner white
(Periphery has the soma and dendrites, GREY while the inner portion has the axon which has the Myelin sheath which is white in colour)

Similarly, spinal cord: outer white, inner grey

Question 38

Unipolar neurons are present in

Answer 38

Embryonal neurons

Question 39

Sponges have what kind of neurons

Answer 39

Trick question haha

Question 40

Parkinson’s and Alzheimer’s are incurable “degenerative” diseases, why?

Answer 40

CNS relates and neurons of CNS are strictly irreparable.

Question 41

Knee jerk reflex stimuli travels where

Answer 41

Dorsal root ganglion (pseudounipolar neuron)

Question 42

Myelinated and non myelinated? Classification of?

Answer 42

Axons

Question 43

Which neuroglial cells form blood brain barrier

Answer 43

Astrocytes

Question 44

Which neuroglial cells repair and form other cells?

Answer 44

Astrocyte