Biological Structures, Nervous, and Muscles. Flashcards Preview

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Flashcards in Biological Structures, Nervous, and Muscles. Deck (25):
1

What is the function of the stratified squamous epithelium cells?

Protection is the main function, especially when it comes to skin.

2

What are the regions of skin?

Epidermis
Dermis
Subcutaneous Tissue

3

What is the function of fibroblast?

Fibroblasts produce help with the production of the extracellular matrix by secretes proteins such as collagen, reticulin, and elastin.

4

Describe the function of the Na/K pump

Pumps 3 Na outside and 2 K inside.

5

What is saltatory conduction?

Action potentials are able to jump alone the axon of the cell in order for the signal to be transmitted even faster.

6

Are the post synaptic membranes voltage gated?

No, AcH binds allowing sodium to pass through and therefore it is considered ligand gated.

7

What are the two types of synapses that can occur at the terminal?

Either an excitatory or inhibitory synapse.

8

What are tendons?

Muscle attached to bone.

9

Describe the different units of the sarcomere:

H: between the two separate actin filaments.
I: area between actin thin filaments.
A: area between myosin thick filaments.
Z: what separates different sarcomeres.

10

Describe muscle contraction

1. In the relaxed state, ATP is bound to the myosin head.
2. ATP is hydrolyzed into ADP which allowed the myosin head to bind to the actin filament.
3. Binding of myosin and actin releases ADP causing for the power stroke to occur.
4. ATP binds to the myosin head to release the myosin from the actin molecule.

11

Describe the tropomyosin, troponin, and calcium complex.

1. Normally, tropomyosin covers the actin filament which prevents myosin from binding to actin.
2. When calcium is present, it binds to troponin which moves tropomyosin.
3. Movement of tropomyosin allows for the binding of myosin to actin.

12

What is the sarcoplasmic reticulum?

Sarcoplasmic reticulum holds calcium in muscle cells for muscle contraction.

13

Describe white and grey matter.

White matter are areas of myelination.
White is outside for spine, but inside for brain.

14

Describe parasympathetic nerve fibers.

Pre Parasympathetic fibers are long
Post Parasympathetic fibers are short
Release Acetylcholine.

15

Compare and contrast somatic and autonomic

Somatic leaves CNS and goes directly to muscle.
Autonomic leaves CNS and may go via ganglions to effector organ.

16

Which bands in the sarcomere changes?

HI

17

Which muscles are involuntary?

Smooth and cardiac.

18

Describe smooth muscle cells

1 nucleus(middle)
No striation

19

Describe cardiac muscle cells

1 or 2 nuclei (middle)
branched
Striations

20

Describe skeletal muscle cells

Multiple nuclei (peripheral)
Striation

21

Contrast Type 1 and Type 2 muscle fibers

m1tochondr1a are more abundant in type 1 .

Type 1 is red, slow contraction, slow twitch, long runs, long term, resistant to fatigue, strong, and store triglycerides.

Type 1 is white, fast contraction, fast twitch, sprinting, short term, easily fatigued, weak force, and uses ATP & creatine phosphate.

22

What controls skeletal muscles?
What controls cardiac/ smooth muscles?

Cortex and Spinal Cord
Brainstem and sympathetic ganglia.

23

Describe thermoregulation via muscles

Signals sent to hypothalamus. Cold is posterior, hot is anterior.

Hot makes smooth muscles relax allowing it to dilate.
Cold makes smooth muscle contract to conserve heat.

24

What is myoglobin?

Holds oxygen in muscle cells.

25

t/f mitochondria have their own ribosomes

true.