Life Sciences Flashcards
1
Q
Which part of the digestive system is where water is primarily absorbed?
A
Colon
2
Q
Which part of the nephron is where re-absorption takes place?
A
Proximal convoluted tubule
3
Q
Correct order in the digestive process?
A
Ingestion, propulsion, mechanical digestion, chemical digestion, absorption and elimination
4
Q
Which part of the brain controls heart beat?
A
Brain stem, medulla oblongata
5
Q
Which endocrine gland produces calcitonin?
A
Thyroid
6
Q
Where do sperm cells mature?
A
Epididymis
7
Q
The small intestine has 3 regions, in which order are they?
A
Duodenum – Jejunum – Ileum
8
Q
Which endocrine gland produces oestrogen?
A
Ovaries
9
Q
The definition of respiration is:
A
Exchange of gases
10
Q
The urethra in females is approximately how long?
A
4cm
11
Q
If the blood glucose concentration is too low, which hormone is released?
A
Glucagon
12
Q
Internal respiration is the:
A
Exchange of gases between blood in systemic capillaries and body cells
13
Q
What receptors are activated during the sense of smell?
A
Chemoreceptors
14
Q
Which part of the eye is the clear window allowing light in?
A
Cornea
15
Q
Which digestive accessory organ produces bile?
A
Liver
16
Q
Which endocrine gland produces Melatonin?
A
Pineal gland
17
Q
Which anterior pituitary hormone in females triggers ovulation?
A
Luteinising hormone (LH)
18
Q
Where does the majority of nutrient absorption takes place?
A
Small intestine
19
Q
The walls of the Gastrointestinal system consist of 4 main layers, which layer consists of epithelial cells?
A
Mucosa
20
Q
Where is sperm produced?
A
Testes
21
Q
Which chamber of the heart is the largest?
A
Left ventricle
22
Q
Where is insulin and glucagon produced?
A
Islet of Langerhans
23
Q
Which structure surrounds the glomerulus?
A
Bowman’s capsule
24
Q
Which type of diabetes does the body still produce insulin but cells can be resistant to the insulin?
A
Type 2
25
Which is the muscle layer of the pericardium?
Myocardium
26
Which endocrine gland produces noradrenalin?
Adrenals
27
How much of blood plasma is made up of water?
91%
28
How many ureters are there in a normal urinary system?
Two
29
What is the thin, smooth membrane which surrounds each lung?
Pleura
30
Which hormone is produced in the kidneys?
Erythropoietin
31
Erythropoietin stimulates:
Red blood cell production
32
Which type of bone is the sternum?
Flat bone
33
Which lymphocytes are involved in the production of antibodies?
B lymphocytes
34
Which endocrine gland produces glucagon?
Pancreas
35
Which endocrine gland produces follicle stimulating hormone?
Anterior pituitary
36
Which part of the ear contains 3 small bones (ossicles)?
Middle ear
37
Where in the reproductive system does fertilization of the egg normally occur?
Fallopian Tubes
38
Layers of the skin
Epidermis, dermis, and the hypodermis
39
Which part of a neurone contains the nucleus?
Cell body
40
Which blood vessels have valves?
Veins
41
Glucagon stimulates:
Breakdown of glycogen in the liver
42
Hypothalamus is linked to posterior pituitary gland by:
Nerve fibres
43
Hypothalamus is linked to anterior pituitary gland by:
Blood vessels
44
What secretes oxytocin and ADH?
Posterior pituitary
45
The thyroid takes ______ from ingested food
Iodine
46
The two thyroid hormones
Tri-iodothyronine (T3)
Thyroxine (T4)
47
What is mitochondria's role in a cell?
Energy supply
48
What are the ribosomes' role in a cell?
Protein synthesis
49
What is rough endoplasmic reticulum studded with?
Ribosomes
50
Three types of muscle tissue
Skeletal, cardiac, smooth
51
The layers of pericardium of the heart (outside -> in)
Epicardium, myocardium, endocardium
52
Which layer of the heart wall contains flat epithelial cells?
Endocardium
53
Period of heart contraction
Systole
54
Period of heart relaxation
Diastole
55
A myocardial infarction (heart attack) happens because of...
A lack of blood flow (and oxygen) to the heart muscle
56
What are the only vessels in which exchange of materials (oxygen and nutrients) between blood and tissues occur?
Capillaries
57
Three layers of an artery (outside-> in)
Fibrous connective tissue, smooth muscle/elastic tissue, endothelium
58
Diameter of a capillary
3-12 micrometres
59
Percentage of blood that is plasma
~55%
60
Percentage of blood that is erythocytes
~45%
61
BP normal range
Systolic - 90-140
Diastolic - 60-90
62
What are the functional units of the lungs where gas exchange takes place?
Alveoli
63
What is a cause of respiratory distress in premature babies?
Sufficient surfactant not produced until 28 weeks gestation
64
What happens is surfactant is absent or reduced?
Alveoli collapse on expiration, increased effort required for inspiration
65
What is external respiration?
Exchange of gases by diffusion between alveoli and pulmonary capillaries
66
What is diffusion?
Movement of gas from a high concentration area to a low concentration area
67
What occurs when the pleural is punctured?
Lung collapse (pneumothorax)
68
In inspiration, what happens to volume of chest cavity?
Increases
69
In inspiration, what happens to pressure in the lungs?
Falls below that of atmospheric pressure
70
On expiration, the diaphragm and intercostal muscles:
Relax
71
On expiration, pressure in the lungs :
Rises
72
The rate of diffusion is proportional to:
Surface area, difference of gas pressure on each side
73
How is the respiratory membrane of the alveoli ideal for gas exchange?
Very thin and a very large surface area
74
COPD is caused by:
Increased resistance or decreased compliance (elasticity)
75
In emphysema, lungs lose:
Their elastic recoil (decreased compliance)
76
In bronchitis, what is wrong with the respiratory tree?
Inner lining is thickened, increase in mucus and goblet cells
77
Gastrointestinal wall layers (outside - > in)
Adventitia, muscle layer, submucosa, mucosa
78
The adventitia is what in the abdomen?
Double serous membrane called the peritoneum
79
What secretes fluid to moisten and lubricate outer surface of GI wall?
Adventitia
80
What can swallowing also be called?
Deglutition
81
What is peristalsis?
The movement of a bolus through the lumen of the GIT by waves of alternate contractions in muscles
82
Gastric juice contains:
Mucus, hydrochloric acid, pepsin
83
What is the principal function of the stomach?
Break down proteins in food to polypeptides
84
How is the stomach GIT wall protected from gastric juice?
Mucus
85
What is the average size of the small intestine in an adult?
3-5 metres
86
What is the function of the duodenum?
Prepares food for absorption using villi
87
What is the function of the jejunum?
Absorption (using enterocytes)
88
What is the function of the ileum?
Absorption of vitamin B, bile salts and everything the jejunum didn't get
89
Where is the pancreas located?
Upper abdomen, behind the stomach, in the spine
90
Where is the liver situated?
Upper right abdomen, just below diaphragm
91
The liver hold 13% of what?
Circulating blood volume
92
What does the liver produce?
Bile (up to one litre per day)
93
What does the liver remove?
Toxins from bloodstream
94
What does the liver metabolise?
Alcohol and some drugs
95
Where is the gallbladder?
Upper right abdomen, under the liver
96
Where does the gallbladder release bile to?
The duodenum (via common bile duct)
97
What does the gallbladder store?
Bile
98
What are the two categories of hormones?
Proteins and lipid
99
What influence cellular activities by binding to receptors?
Hormones
100
What is negative feedback?
Effector response decreases the effect of original stimulus
101
What should blood glucose levels be maintained at?
90mg/100ml
102
If blood glucose level is too high, what does the pancreas produce?
Insulin
103
Insulin increases the uptake of _______ into cells
Glucose
104
Insulin enhances the storage of ________ in the liver
Glycogen
105
Insulin inhibits the conversion of ________ and _______ into glucose
Amino acids and fatty acids
106
What is direct hormone release?
Levels of chemicals in blood act directly on endocrine gland
107
What is indirect hormone release?
Release of other hormones secreted by hypothalamus and anterior pituitary gland
108
What does oxytocin act on?
Smooth muscle of uterus and milk ducts
109
What does ADH act on?
Kidneys, to reduce urine volume
110
What gland controls calcium levels in blood?
Thyroid and parathyroid
111
What does melatonin control?
Biorhythms
112
Which hormone does the thymus produce?
Thymosin
113
What function does thymosin help?
Development of immune system
114
What hormones do the digestive system produce?
Gastrin, secretin, cholecystokinin
115
Which endocrine gland produces thyroid stimulating hormone?
Anterior pituitary gland
116
Endocrine gland secretions are discharged into the _____ or ______ directly
Blood or lymph
117
The peripheral nervous system is split into what two types of nerves?
Sensory (afferent) and motor (efferent)
118
What is the function of the neurone's dendrite?
Convey information to neurone's cell body
119
What is the function of the neurone's axon?
Convey information away from neurone's cell body
120
What is the function of the neurone's nerve terminal?
Send messages to next cell
121
What is a neurone's grey matter?
Cell body
122
What is a neurone's white matter?
Axons and dendrites
123
How many neurones are involved in impulse transmission?
Always more than one
124
There is no __________ between neurones
Physical contact
125
What is a synapse?
The short gap between neurones
126
A nerve impulse arriving at the synapse causes the release of what?
Neurotransmitters
127
What do neurotransmitters bind to?
Receptors in the postsynaptic cell
128
What can postsynaptic cells be?
Neurone, muscle, gland
129
The effect on postsynaptic cell can be:
Excitatory or inhibitory
130
What two ways are neurotransmitters removed from synaptic cleft?
Enzyme breakdown,
Or transported back into presynaptic neurone
131
What are the two types of motor (efferent) nerves?
Somatic (voluntary) and autonomic (involuntary)
132
What does the autonomic nervous system control?
Cardiac, smooth muscle and glands
133
What two ways can the autonomic nervous system be divided?
Sympathetic and parasympathetic
134
Which nervous system reacts to emergency situations?
Sympathetic, with fight or flight response
135
Which nervous system reacts to non-emergency situations to allow for rest and digestion?
Parasympathetic
136
What three parts is the brain made up of?
Cerebrum, cerebellum, brainstem
137
Which part of the brain initiates and controls muscle contractions?
Cerebrum
138
Which part of the brain coordinates voluntary movements, posture and balance?
Cerebellum
139
What part of the brain controls breathing and heart beat?
Brainstem
140
What is the relay between the spinal cord and higher brain?
Brainstem
141
The spinal cord carries what information from body to brain?
Sensory (afferent)
142
What is responsible for reflex actions?
Spinal cord
143
What bones protect the CNS?
Skull and vertebrae
144
What are the meninges?
Three membranes that envelop brain and spinal cord
145
What three things protect the CNS?
Bone, meninges and cerebrospinal fluid
146
What are the two broad categories of defence in the immune system?
Innate/non-specific and specific (immune system)
147
What is the first line of innate defence?
Mechanical barriers (such as the skin, mucous membranes, mucus, hairs, gastric acid, lysozyme in tears, acid pH of skin)
148
What are two second lines of innate defence?
Internal mechanisms (phagocytic (cell eating) white blood cells, antimicrobial proteins, fever) AND the inflammatory response
149
What does the inflammatory response respond to?
Tissue damage such as cuts, burns, bacterial and viral invasion.
150
What are the 4 cardinal signs of the inflammatory response?
Pain, redness, swelling and heat
## Footnote
Sometimes a fourth – loss of function is also included
151
The inflammatory response results in:
Increased blood flow, dilation, increased permeability of blood vessels, exudation of fluids
## Footnote
Exudation = oozing
152
What two distinguishing characteristics does the immune response have?
Specifity and memory
153
Define "specificity" in relation to the immune response.
Each response is particular to the one particular foreign material that has caused it to occur
154
Define "memory" in relation to the immune response
A second encounter provokes a much more rapid and vigorous immune response than that which was elicited on first exposure, thus causing rapid and successful elimination of the material
155
Where are lymphocytes found in greatest density?
The bone marrow, spleen, lymph nodes and thymus
156
Where do B lymphocytes mature?
Bone marrow
157
What produces antibodies?
B lymphocyte
158
B lymphocytes are involved in what immune response?
Antibody-mediated/humoral
159
T lymphocytes are involved in what immune response?
Cell-mediated
160
Where do T lymphocytes mature?
Thymus
161
Which lymphocytes attack foreign material more directly?
B lymphocytes
162
What is an antigen?
A substance on outer surface of cells, "a unique label"
163
What on invading organisms provokes an immune response?
Antigens
164
What are antigens usually formed of?
Big molecules - proteins or their derivatives
165
What is an antibody also known as?
Immunoglobulin
166
Each B lymphocyte produces only one particular _______
Antibody
## Footnote
This is capable of binding to only one antigen
167
What is the lymphatic system comprised of?
An extensive network of blind-ended lymph vessels originating in interstitial space between cells
168
Three main functions of the lymphatic system
Tissue drainage, fat absorption and immunity
169
What three things does the lymphatic system consist of?
- Lymph
- Lymphatic vessels
- Lymphatic tissue (nodes)
170
What form does a lymph have?
Clear watery fluid
## Footnote
Fluid similar in composition to interstitial (tissue) fluid
171
The lymph returns the small amount of _ that seeps into the interstitial space back to the circulation
Plasma protein
172
All tissues have a network of lymphatic vessels except for ____ and ___
Bone and CNS
173
Where are lymphatic capillaries found?
Close to nearly every cell in the body
174
What is the function of lymphatic capillaries?
Collect up excess tissue fluid
175
What is the function of larger lymph vessels?
Transport collected tissue fluid back to the veins of the CVS
176
Which type of lymphatic vessel has valves?
Larger lymph vessels
177
How are lymphatic ducts formed?
Lymph vessels joining together
178
What are the three main types of lymphatic vessels?
- Lymphatic capillaries
- Larger lymph vessels
- Lymphatic ducts
179
What are the function of lymphatic nodes?
To filter and "clean" lymph before return to circulation
180
Several ____ _______ will enter a lymphatic node, but only one ____ ______will leave the node
Lymph vessels
181
Nodes contain many _________ and _________.
Lymphocytes and macrophages
182
What does the lymph node remove?
Particulate matter
## Footnote
e.g. bacteria and cell debris
183
Where are large nodes of lymphatic tissue present in?
Tonsils, appendix & small intestine
184
Where are lymphocytes produced?
Bone marrow
185
What is the structure and location of the thymus?
Large gland consisting of 2 lobes in the neck
186
When is the thymus most active?
In childhood
187
What is the largest lymph organ?
Spleen
188
Where is the spleen located?
Behind stomach
189
Four functions of the spleen:
◦ Cleaning blood of microorganisms and old RBCs
◦ Storing blood
◦ Site where lymphocytes re activated
◦ Important site of blood cell production in foetus
190
What is the composition of urine?
96% water, 2% urea and some sodium chloride
191
What is the function of the ureters?
Transport urine from kidneys to bladder?
192
What is the function of renin?
Blood pressure regulation
193
What two hormones do the kidneys produces?
Erythropoietin and renin
194
What is a nephron?
The functional unit of the kidney which produces urine
195
Approximately how many nephrons are there per kidney?
One million
196
In which part of the kidney is the nephron found?
Cortex and medulla
197
How are the nephrons arranged?
In renal pyramids
198
What is important for concentrating urine?
Loop of Henle
199
Urine formed in the nephrons is collected where?
Renal pelvis
200
What connects to the collecting duct of a nephron?
Distal convoluted tubule
201
What are the three processes of urine formation?
* Glomerular filtration
* Tubular selective reabsorption
* Tubular secretion
202
What is and isn't filtered in glomerular filtration?
Water & small molecules filtered, blood cells & plasma proteins are not
203
What affects the filtration of blood through the glomerular capillary walls?
Blood pressure
204
Where does blood arrive via in the glomerulus?
Afferent arteriole
205
Where does blood exit via in the glomerulus?
Efferent arteriole
206
How many litres of filtrate is formed per day in the glomerulus?
200 litres
207
What is the typical blood volume for an adult?
5 litres
208
How is it possible to form 200L of filtrate from only 5L of blood?
Only 1 L/day is typically excreted from the body as urine; the remainder is reabsorbed
209
What is selective tubular reabsorption?
Reabsorption of important constituents of filtrate back into blood
210
What is normally completely reabsorbed in selective tubular reabsorption?
Glucose
211
Reabsorption of what substance is regulated to maintain balance in tubular reabsorption?
Sodium
212
Tubular secretion is in the opposite direction to what?
Reabsoprtion
213
Hydrogen ion secretion removes what?
Excess acid from body
214
Hydrogen ion secretion helps control what?
Blood pH
215
What is the normal blood pH in humans?
7.35 to 7.45
216
What does antidiuretic hormone (ADH) do to the collecting ducts?
Increases permeability of walls
217
What is the effect of ADH?
* Water reabsorption increases
* Urine becomes more concentrated
218
What is another word for urination?
Micturition
219
What are the four layers of the bladder wall?
Outer, middle, detrusor muscle, inner
220
What is the function of detrusor muscle?
It contracts to make the bladder empty
221
How long is the urethra in males?
20cm
222
What is the internal urethral sphincter?
A ring of smooth muscle at the exit of the bladder
223
What is the external urethral sphincter?
A ring of skeletal muscle at the exit of the bladder
224
What causes the relaxation of internal urethral sphincter?
Parasympathetic nervous system
225
What prevents unwanted urination?
Voluntary contraction of external urethral sphincter
226
How is the desire to urinate felt?
Stretch receptors send signals to brain
227
How does micturition happen in babies?
Bladder gets full, initiates a spinal reflex
228
What are two causes of incontinence?
- Damage to nerves controlling bladder
- Disease of bladder or urethra
229
What are two alternative names for the testes?
Testicles or gonads
230
Where are the testes located?
Suspended outside the body in the scrotum
231
Why are the testes suspended outside the body in the scrotum?
To maintain a suitable temperature conducive to sperm production
232
What is the function of the vas deferens?
Transports mature sperm to the urethra
233
What is the prostate gland's function?
To produce and secrete fluid that mixes with sperm to create semen.
234
What are the seminal vesicles attached to?
Vas deferens
235
What do the seminal vesicles produce?
A sugar-rich fluid that provides energy to sperm
236
What carries sperm out of the body?
Urethra
237
How many sperm are contained per ml of ejaculate?
50 million to 100 million
238
Most men produce around how many of ml per ejaculation?
1.5 – 5ml
239
Where is DNA located in the sperm?
Head
240
What is located in the midpiece of the sperm to give energy?
Mitochondria
241
What is fertilisation?
The fusion of male and female gametes (sperm and egg)
242
What is another word for sperm?
Spermatozoa
243
What is another word for an egg?
Oocyte
244
What is the result of the fusion of male and female gametes?
A zygote
245
Egg cells always carry which chromosone?
X
246
Close to labour, what happens to the cervix?
Softens and gets thinner,
247
What causes labour contractions?
Baby’s head pushing down on the cervix and release of oxytocin
248
What is grown in the uterus to help support a fertilised egg?
Endometrium
249
What are the two phases of the menstrual cycle?
Follicular and luteal
250
What happens to the uterine lining during the proliferative phase?
Regenerated - in preparation for a fertilised egg
251
When is the secretory phase of the menstrual cycle?
Days 15-28
252
Which part of the skeleton is the skull part of?
Axial
253
Which type of shock is caused by anaphylaxis?
Distributive
254
Which pulse rate is called tachycardia?
>100bpm
255
What provides UV protection to the skin?
Melanin
256
Which structural level of organisation in the human body includes atoms and molecules?
Chemical
257
Where would you find smooth muscle?
Walls of the digestive tract, bladder, various ducts, arteries and veins and other internal organs
258
What controls skeletal muscle?
Somatic nervous system
259
What type of muscle can also be called voluntary or striated muscle?
Skeletal muscle
260
What controls cardiac muscle?
Autonomic nervous system
261
What bone system form the axis of the body ?
Axial
262
What bones are part of the axial system?
Skull, sternum, ribs and vertebral column
263
What are osteoblasts?
Mono-nucleate bone forming cells
264
What are the functions of osteocytes?
Bone formation, matrix maintenance and calcium homeostasis
265
What is the function of osteoclasts?
Bone destroying (or bone-resorption) cells, responsible for remodelling bone when necessary
266
What type of bone are the femur and tibia?
Long
267
What type of bone are the carpus and patella?
Short
268
What type of bone are the sternum and scapula?
Flat
269
What type of bone are the vertebrae and maxilla?
Irregular
270
Where would you find a sesamoid bone?
In a tendon
271
What are five basic tissues comprising the musculoskeletal systems?
- Bones
- Ligaments
- Cartilage
- Skeletal Muscles
- Tendons
272
What are the two types of joint?
- Structural – fibrous, cartilaginous and synovial
- Functional – synarthroses, amphiarthroses and diarthroses
273
What are the classification of joints from immovable to moveable?
Synarthroses, amphiarthroses and diarthroses
274
What is an example of a ball and socket joint?
Hip joint
275
What is an example of a hinge joint?
Elbow joint
276
What is an example of a pivot joint?
Wrist joint
277
What is an example of a gliding joint?
Intervertebral joints
278
What is an example of a saddle joint?
Thumb joint
279
What is an example of a condyloid joint?
Finger joints
280
What is the largest and heaviest organ?
Skin
281
What are the three layers of skin?
Epidermis, dermis, hypodermis/subcutaneous
282
What is the epidermis made up of?
Stratified squamous epithelium
283
What many layers of epidermis does thick skin have?
Five
284
What produces epidermal/skin colour?
Melanin
285
What produces melanin?
Melanocytes
286
The epidermis activates the synthesis of what?
Vitamin D3
287
Where do hair follicles lie?
Dermis
288
What is the dermis mainly made up of?
Dense connective tissue
289
What is the hypodermis mainly made up of?
Loose connective and adipose tissue
290
What specialised epithelial gland produces sebum?
Sebaceous gland
291
What is sebum?
Oily mixture that keep hair and skin soft, pliable and waterproof
292
What are sebaceous glands attached to?
Hair follicles
293
What is a sweat gland also known as?
Sudoriferous gland
294
What are the two types of sweat gland?
Eccrine and apocrine
295
What do the eccrine glands respond to?
Heat
296
What do the apocrine glands respond to?
Emotion
297
What is hyperhydrosis?
Overactive sweat glands in hands, feet and armpits
298
What causes hyperhydrosis?
Overactive nervous system
299
What are the five special sense?
Sight, hearing, taste, smell, touch
300
What part of the eye contains photoreceptors?
Retina
301
What are the two types of photoreceptor?
Rod and cone
302
What are the rods sensitive to?
Dim light
303
What are the cones sensitive to?
Bright light and colour
304
What is the name of the white of the eye?
Sclera
305
What is the name of the smooth muscle which regulates pupil size?
Aperture, or pupil
306
What focuses light on the retina?
Lens
307
Where is the ciliary body found?
Behind the iris
308
What is the structure and function of the ciliary body?
Ring-shaped muscle that changes the shape of the lens when the eye focuses
309
What is the name of the fluid in the eye?
Humor
310
Sound causes what to vibrate in the outer ear?
Tympanic membrane
311
What part of the ear houses the cochlea?
Inner ear
312
What sends information to brain about head position and contribute to maintenance of balance?
Semi-circular canals
313
Where taste buds found?
Tongue, throat and epiglottis
314
Where are the receptors for touch found?
Skin and mucous membrane
315
What are the two types of touch receptors?
Meissner’s corpuscle and Pacinian corpuscle
316
What does Meissner’s corpuscle detect?
Light touch
317
What does the Pacinian corpuscle detect?
Pressure
318
Which blood vessel brings blood to the glomerulus?
Afferent arteriole
319
Which layer of the skin are hair follicles situated?
Dermis
320
What is the normal pH range of urine?
4.5-8
321
Which are the 3 basic components of a control system?
Receptor, control center, effector
322
During swallowing, which structure closes over the airway to protect from aspiration?
Epiglottis
323
What type of tissue binds, supports and protects?
Connective tissue
324
Which part of the ear amplifies the sound waves?
Middle ear
