topic 1 (brain cells and types)

Question 1

How many neuronal cells are there in the human brain?

Answer 1

85 billion

Question 2

how many non neuronal cells are there in the human brain?

Answer 2

85 billion

Question 3

what percentage of the cell is water and what percentage is organic/inorganic molecules?

Answer 3

70% water
30% organic/inorganic molecules

Question 4

how many human genes does DNA code for per cell?

Answer 4

23,000

Question 5

how many protein molecules are there per cell?

Answer 5

42 million

Question 6

how many lipid molecules are there per cell?

Answer 6

1000

Question 7

what different molecules are there in each cell?

Answer 7

nucleic acids
proteins
lipids
polysaccharides
inorganic ions
water

Question 8

what is the most abundant molecule in the cell?

Answer 8

proteins

Question 9

what are the two stages of DNA coding for protein

Answer 9

Transcription- DNA making a messenger RNA molecule
Translation- mRNA being translated into a protein

Question 10

what is guanine always opposite?

Answer 10

cytosine

Question 11

what is adenine always opposite

Answer 11

thymine

Question 12

how many amino acids are there?

Answer 12

22

Question 13

what does phosphoryation/dephospohrylation do?

Answer 13

phosphorylation and dephosphorylation can be used by a cell to switch on and off the function of a protein

Question 14

what is a cytoskeleton?

Answer 14

• a system of filaments or fibres present in the cytoskeleton
• it maintains the cells shape and helps with the movement of organelles within the cell

Question 15

what is the proteasome?

Answer 15

-a large protein complex responsible for the degradation of intracellular proteins

• they degrade unneeded or damaged proteins
• they do this by proteolysis- a chemical reaction that breaks protein bonds

Question 16

what are 5 major cell types of the brain?

Answer 16

• neurons
• astrocytes
• oligodendrocites
• migroglia
• endothelial

Question 17

what are 7 additional minor cell types of the brain?

Answer 17

• smooth muscle
• pericytes
• vascular leptomeningeal cells
• epyndemal cells
• epithelial cells
• lymphocytes
• schwann cells

Question 18

what does post-mitotic mean?

Answer 18

they do not divide any further

Question 19

what is apoptosis?

Answer 19

programmed cell death

Question 20

what is a protein uniquely expressed by neurons?

Answer 20

neurofilament proteins

Question 21

what is the developmental origin of oligodendrocytes?

Answer 21

the neuroectoderm

Question 22

what cells do oligodendrocytes develop from?

Answer 22

neuronal stem cells and oligodendrocyte progenitor cells

Question 23

what are the express marker proteins of oligodendrocytes?

Answer 23

NG2, olig1, MBP, PLP, MOG

Question 24

what is the origin of astrocytes in the neural tube?

Answer 24

the neuroectoderm

Question 25

what are 5 functions of astrocytes?

Answer 25

• regulation of synaptic connectivity
• regulation of neurotransmitter homeostasis in the extracellular space
• they link together in a network at the edge of cappileries to help form the blood brain barrier
• they help guide circuit formation during development
• they are involved in wound healing and limitation of inflammation

Question 26

what are the express markers of astrocytes?

Answer 26

GFAP, vlimentin, GLAST

Question 27

where do microglia develop from?

Answer 27

• myeloid progenitors in the blood island in the yolk sac
• they are formed from the first wave of haemopoeisis

Question 28

what are the functions of microglia?

Answer 28

• they eat dying or dead cells
• they kill and engulf pathogens
• they have been shown to nibble the membranes of neuronal cells as part of normal brain function. This potentially impacts the remodelling of synaptic neural networks

Question 29

what is the main express marker protein of microglia?

Answer 29

iba-1