Topic 7 ~ Run For Your Life

Question 1

Definition of antagonistic

Answer 1

A pair of muscles that work together as muscles can only pull so 2 are needed to move a bone to and fro

Question 2

What is an extensor muscle

Answer 2

A muscle that contracts to cause extension of a joint

Question 3

What is a flexor muscle

Answer 3

A muscle that contracts to reverse the movement of extensor muscles

Question 4

What is synovial fluid

Answer 4

Fluid found in a cavity within a joint that lubricates the bones enabling them to move freely

Question 5

What is the function of ligaments in a joint

Answer 5

Joins bone to bone

Strong and flexible

Question 6

What is the function of the synovial membrane

Answer 6

It secretes synovial fluid

Question 7

What is the function of the tendon in a joint

Answer 7

Joins the muscle to bone

Question 8

What is the function of cartilage in a joint

Answer 8

Absorbs synovial fluid

Acts as a shock absorber

Question 9

What is the function of pads of cartilage

Answer 9

Gives additional protection

Question 10

What is the function of the fibrous capsule

Answer 10

Encloses the joints

Question 11

What are muscle fibres and their adaptations

Answer 11

Single muscle cells
Long in length
Each has several nuclei

Question 12

Why do muscle fibres have several nuclei

Answer 12

A single nucleus could not effectively control the metabolism of such a long cell

Question 13

What’s the structure of muscle fibres

Answer 13

Bundles of myofibrils that is made up of repeated units of sarcomeres

Question 14

Structure of sarcomeres

Answer 14

Made up of 2 types of protein

• actin (thin)
• myosin (thick)

Question 15

What happens to sarcomere when the muscle contracts

Answer 15

The actin moves between the myosin, shortening the length of the sarcomere and therefore the length of the muscle

Question 16

What is the role of calcium in muscle contraction

Answer 16

• Calcium released from sarcoplasmic reticulum
• diffuses through sarcoplasm
• attaches to troponin causing it and tropomyosin to move, exposing the myosin binding sites

Question 17

Describe the sliding filament theory

Answer 17

• calcium attaches to troponin causing it and tropomyosin to move, exposing the myosin binding sites
• myosin heads bind forming crossbridge
• ADP and Pi are released
• myosin head nods forward moving the actin towards centre of sarcomere
• ATP binds to myosin head causing it to detach from actin
• ATPase hydrolyses ATP forming ADP and Pi
• myosin head returns to upright position

Question 18

What is BMR (basal metabolic rate)

Answer 18

Measure of the minimum energy requirement of the body at rest to fuel basic metabolic processes

Question 19

How is BMR measured

Answer 19

By recording oxygen consumption

• no food consumed for 12 hours
• body totally at rest
• in a thermostatically controlled room

Question 20

Why is glucose and oxygen not brought together directly and instead split in several steps

Answer 20

Because it would release very large amounts of energy quickly which would damage the cell

Question 21

Describe the process of glycolysis

Answer 21

• glycogen is hydrolysed to glucose 6C
• 2Pi is added to glucose from 2 ATP molecules
• glucose is split into 2x phosphorylated 3C compounds
• each intermediate is oxidised to 3C pyruvate
• 2 hydrogen atoms are removed and reduce NAD
• 4ATP is formed as 2Pi from intermediate is transferred to 4ADP and 2Pi

Question 22

What is substrate-level phosphorylation

Answer 22

When energy for the formation of ATP comes from the substrates
(ATP directly made)