bio topic 11

Question 1

What can occur as a result of exposure to an allergen such as pollen?

Answer 1

White blood cells release histamine

Question 2

What is fused with tumour cells in the production of monoclonal antibodies?

Answer 2

Plasma cells

Question 3

A secondary immune response occurs when an antigen is encountered on a second occasion, due to exposure to a pathogen that previously caused infection. Which property of some viruses explains the lack of a secondary immune response?

Answer 3

Viruses have a high mutation rate

Question 4

Cetuximab is a type of monoclonal antibody used to treat cancers of the large intestine. How are these monoclonal antibodies obtained?

Answer 4

From hybridoma cells produced by fusion of tumour cells and plasma cells

Question 5

When activated B cells multiply, what do they produce?

Answer 5

Plasma cells

Question 6

How are monoclonal antibodies produced?

Answer 6

Fusion of plasma cells with tumor cells

Question 7

What is required for a skeletal muscle to exert force?

Answer 7

Attachment to bones

Question 8

Which events lead to the production of antibodies?

Answer 8

T lymphocytes activate the B lymphocytes that then create a clone of memory cells and a clone of plasma cells that create antibodies

Question 9

What is an example of active immunity?

Answer 9

Antibodies produced after the defence mechanisms have been stimulated by antigens

Question 10

What results from the fusion of tumour cells with B-cells?

Answer 10

The production of monoclonal antibodies

Question 11

In the production of monoclonal antibodies, B-cells are fused to tumour cells to make hybridoma cells. What can hybridoma cells do?

Answer 11

Divide endlessly

Question 12

How are B-cells activated?

Answer 12

An antigen binds to a B-cell which is activated by a helper T-cell.

Question 13

What is clonal selection?

Answer 13

Mitotic division of B cells activated in response to an infection

Question 14

What is required to produce monoclonal antibodies?

Answer 14

B-lymphocytes and tumour cells

Question 15

When a pathogen is ingested by a phagocyte, which event occurs first?

Answer 15

Antigen presentation by the phagocyte

Question 16

Which cells activate helper T-cells by antigen presentation?

Answer 16

Macrophages

Question 17

What first happens to a B lymphocyte when it becomes activated?

Answer 17

It divides by mitosis producing a clone of cells

Question 18

Where do calcium ions that are released from the sarcoplasmic reticulum bind to stimulate

Answer 18

Troponin on actin filaments

Question 19

What occurs during inspiration?

Answer 19

External intercostal muscles contract, decreasing the pressure in the thorax.

Question 20

What is contained in skeletal muscle?

Answer 20

Multinucleate cells with numerous microfibrils made of contractile sarcomeres

Question 21

What is the order of increasing size of muscle structures?

Answer 21

sarcomere, myofibril, muscle fibre, muscle

Question 22

What are features of both endoskeletons of mammals and exoskeletons of insects?

Answer 22

They are both moved by antagonistic sets of muscles.

Question 23

What is the role of the joint capsule in an elbow joint?

Answer 23

It seals the joint to retain the synovial fluid.

Question 24

What is the role of calcium ions in muscle contraction?

Answer 24

To bind to troponin, exposing myosin-binding sites on actin

Question 25

Which process is part of the mechanism that controls muscle contraction?

Answer 25

Calcium frees actin filaments for myosin heads to attach.

Question 26

What is the main role of nerves in human movement?

Answer 26

To cause muscle contraction

Question 27

A skeletal muscle contains bundles of elongated muscle fibre cells. What is the longest structure within each fibre?

Answer 27

A myofibril

Question 28

What is the role of ATP during contraction of a skeletal muscle fibre?

Answer 28

To break cross-bridges and re-set myosin heads

Question 29

Which is the sequence of events in muscle contraction? I. Use of ATP II. Formation of cross bridges III. Release of calcium ions from the sarcoplasmic reticulum IV. Actin filament moves towards the centre of the sarcomere

Answer 29

III -> II -> IV -> I

Question 30

What is the role of calcium ions during muscle contraction?

Answer 30

To move the molecules blocking the myosin binding site on actin

Question 31

What is the role of ligaments in humans?

Answer 31

To hold bones together

Question 32

Which of the following is a term for muscle cell?

Answer 32

Muscle fibre

Question 33

During muscle contraction, what is the role of calcium ions ( Ca2+) which are released from the sarcoplasmic reticulum?

Answer 33

To cause binding sites on the actin filaments to be uncovered

Question 34

Where is the greatest quantity of water reabsorbed from the nephron?

Answer 34

Proximal convoluted tubule

Question 35

Where does ultrafiltration happen in the nephron?

Answer 35

Glomerulus and Bowman's capsule

Question 36

What sequence shows the route taken by nitrogenous wastes in insects from their production in body cells to their removal from the insect’s body?

Answer 36

Hemolymph → Malpighian tubule → hindgut → rectum

Question 37

Where in the nephron is most glucose reabsorbed?

Answer 37

Proximal convoluted tubule

Question 38

What facilitates the formation of glomerular filtrate?

Answer 38

Many fenestrations in walls of capillaries in the glomerulus

Question 39

Which hormone influences movement of water into blood?

Answer 39

ADH

Question 40

What is the effect of ADH on the kidney?

Answer 40

It stimulates reabsorption of water in the collecting duct

Question 41

The presence of proteins such as albumin in a urine sample indicates kidney damage. Where in the kidney would the damage exist?

Answer 41

Cortex

Question 42

What is the nitrogenous waste excreted in insects?

Answer 42

Uric acid

Question 43

Damselflies are flying insects. They lay eggs that hatch into larval forms that are aquatic. Adults excrete uric acid while the larval forms excrete ammonia. What is a possible explanation of this?

Answer 43

Uric acid can be excreted in a more concentrated form than ammonia.

Question 44

Dialysis fluid is similar to normal blood plasma. What would be in solution in the dialysis fluid?

Answer 44

Sugar and salts only

Question 45

Glucose moves from the filtrate in the nephron into the bloodstream during normal kidney function. Which location and method describe this movement of glucose?

Answer 45

Proximal convoluted tubule via active transport

Question 46

What is the function of the loop of Henle?

Answer 46

To maintain a hypertonic solution in the medulla

Question 47

What is normally found in the urine of a healthy individual?

Answer 47

Sodium ions

Question 48

Which kidney adaptation would be expected in the desert kangaroo rat (Dipodomys deserti)?

Answer 48

Longer loop of Henle

Question 49

In which region of the kidney is the glomerulus found?

Answer 49

Cortex only

Question 50

In what part of the nephron would most glucose be reabsorbed?

Answer 50

Proximal convoluted tubule

Question 51

Where are microvilli located in the nephron?

Answer 51

Proxital convoluted tubule

Question 52

In a mammal that had just ingested a large volume of water, what would be secreted into the bloodstream?

Answer 52

Less ADH (vasopressin)

Question 53

What is the function of cortex?

Answer 53

Ultrafiltration

Question 54

During urine production, what happens if the water content of the blood is too low?

Answer 54

Membrane channels are produced in the cells of the collecting duct.

Question 55

Which half of the loop of Henlé permeable to sodium?

Answer 55

The second one

Question 56

What would result from drinking large quantities of water?

Answer 56

ADH would not be secreted and the permeability of the collecting duct to water would decrease

Question 57

Which processes are required for the reabsorption of glucose in the kidney tubules?

Answer 57

Facilitated diffusion and active transport

Question 58

Which structure is acted upon by ADH (vasopressin)?

Answer 58

The loop of Henlé

Question 59

Which of the following best describes what happens in the glomerulus?

Answer 59

High blood pressure forces water and other molecules into the tubule lumen

Question 60

At what stage of spermatogenesis does the first division of meiosis occur?

Answer 60

Primary spermatocyte to secondary spermatocyte

Question 61

At what stage of spermatogenesis does the first division of meiosis occur?

Answer 61

Primary spermatocyte to secondary spermatocyte

Question 62

Which statement applies to the placenta?

Answer 62

Carbon dioxide diffuses from fetus to mother across the placenta.

Question 63

What happens in the acrosome reaction?

Answer 63

Enzymes digest the zona pellucida around an ovum, allowing a sperm to enter.

Question 64

Hormones maintain the thickness of the endometrium during pregnancy. However, insufficient levels of hormones in early pregnancy may cause the breakdown of the endometrium, which leads to miscarriage. What could be a cause of miscarriage in early pregnancy?

Answer 64

The embryo does not produce enough HCG (human chorionic gonadoprotein)

Question 65

What is the role of HCG in early pregnancy?

Answer 65

It prevents the degeneration of the corpus luteum in the ovary.

Question 66

Which mechanism prevents polyspermy?

Answer 66

The cortical reaction

Question 67

What is a cortical reaction?

Answer 67

It is a calcium-dependent exocytotic process in which the content of secretory granules is released into the perivitellin space immediately after fertilization

Question 68

What hormone is secreted the least by the end of pregnancy?

Answer 68

Progesterone

Question 69

What hormone is secreted the most by the end of the pregnancy?

Answer 69

Prolactin

Question 70

What function is maintained as a result of the release of HCG?

Answer 70

Production of progesterone by the ovary

Question 71

The pregnancy test for humans is based on detection of the hormone HCG. What is the reason for detection of this hormone indicating pregnancy?

Answer 71

HCG is produced by an embryo.

Question 72

What does the blastocyst secrete?

Answer 72

HCG

Question 73

The diagram shows the exchange processes that take place in the placenta between the maternal and fetal blood. Which process requires endocytosis?

Answer 73

Transfer of immunoglobulins from mother's blood to fetal's blood

Question 74

Which hormone is inhibited during pregnancy in order to prevent contractions of the uterus?

Answer 74

Oxytocin

Question 75

What is the function of the epididymis in the male reproduction system?

Answer 75

To store the sperm in the final stages of maturation

Question 76

Which event takes place during normal fertilization?

Answer 76

The cortical granules fuse with the egg membrane

Question 77

Through what process does a spermatid become a functioning spermatozoan?

Answer 77

Differentiation

Question 78

What is the role of HCG (human chorionic gonadotrophin) in early pregnancy?

Answer 78

It maintains the corpus luteum

Question 79

What is the correct order of events in fertilization?

Answer 79

acrosome reaction, fusion of gametes and then cortical reaction

Question 80

What is secreted after implantation of the blastocyst in the uterine wall?

Answer 80

HCG which prevents the degeneration of the corpus luteum

Question 81

Which statement about the human placenta is incorrect?

Answer 81

The mother’s blood and the baby’s blood mix in the placenta.

Question 82

What is a blastocyst?

Answer 82

The embryo when it has become a hollow ball of cells

Question 83

What is the role of testosterone in spermatogenesis?

Answer 83

I inhibits Sertoli cells

Question 84

What is the role of epididymis in the production of semen?

Answer 84

Maturation of sperm

Question 85

What is the role of seminal vesicle in the production of semen?

Answer 85

Production of fructose

Question 86

What is the role of prostate gland in the production of semen?

Answer 86

Production of fluid containing alkaline minerals

Question 87

What statement describes oogenesis?

Answer 87

One egg is produced per meiosis every 28 days