Digestion and nutrition Flashcards
(146 cards)
1
Q
The neural and hormonal pathway that trigger the release of the gastric juice
A
sensory receptors→ vagus nerve→brainstem→vagus nerve→g cells→gastrin →gastric juice
2
Q
The components of the gastric juice
A
Hydrochloric acid/ intrinsic factors/ pepsinogen/ mucus
3
Q
what cells secrete hydrochloric acid and intrinsic factors in the stomach?
A
Parietal cells
4
Q
What cells secrete pepsinogen?
A
Chief cells
5
Q
what are the special adaptations in the stomach wall structure?
A
Oblique muscle and the opening of the gastric glands
6
Q
what’s the function of the intrinsic factors?
A
absorption of B12
7
Q
The function of HCl in the stomach
A
produces a pH of 2 for pepsine , breaks down large food, kills bacteria taken in food
8
Q
The functions of the small intestine
A
Digestion and absorption
8
Q
what substances are digested in the small intestine
A
Carbohydrates, Fats and proteins
8
Q
Give an account of carbohydrate digestion in the small intestine
A
pancreatic amylase break down starch to maltose, the small intestine secretes maltase to further break down the maltose.
9
Q
Name the regions of the small intestine
A
Duodenum, Jejunum, ileum.
10
Q
what are the adaptions in the small intestine?
A
1/ the folds and villi in the wall increase the surface area 2/ the wall of the villi is one cell thick and has an abundance of transporter proteins and microvilli making the absorption more efficient 3/ Lacteal and blood capillaries under the one cell thick epithelial.
11
Q
name the major carbohydrate digestive enzymes?
A
Salivary amylase, Pancreatic amylase, intestinal enzymes.
11
Q
name the enzymes that break polysaccharides to disaccharides
A
Salivary amylase, pancreatic amylase
12
Q
Name the enzyme that break down maltose to glucose
A
Maltase( intestinal enzyme)
13
Q
Name the enzymes that break down proteins?
A
pepsin, trypsin, chymotrypsin
14
Q
enzymes that break down proteins to peptides
A
pepsin, trypsin, chymotrypsin
15
Q
enzyme that break down peptides to amino acids
A
intestinal enzymes
16
Q
The enzyme that break down lipids
A
Lipase
17
Q
The products of breaking down lipids
A
free fatty acids, glycerol
18
Q
Site of enzyme action in the small intestine
A
Glycocalynx
19
Q
The location of goblet cells in the small intestine
A
crypt of leiberkuhh
20
Q
The pancreas function
A
Exocrine function. secretes digestive enzymes and bicarbonate.
21
Q
The function unit of the pancreas
A
Lobule
22
what is lobule
clusters of acini cells that secrete digestive enzymes
23
The endocrine cells of the pancreas
Islet of Langerhans
24
The cells that secretes insulin and glucagon
Islet of Langerhans
25
The two inactive protease precursors:
Trypsinogen and chymotrypsinogen
26
What enzyme activates the inactive protease precursor from the pancreatic juice?
enterokinase secreted by the duodenum wall
27
The components of the pancreatic juice
Lipase, Amylase, trypsinogen, chymotrypsinogen, Bicarbonate
28
The lipase partner in crime in breaking down fats?
Bile salts
29
Trypsin is more focused on the bonds that follow:
Lysine and Arginine
30
The function of the bile produced from the liver
The bile emulsifies fats preparing them for lipase.
31
Name the two bile salts
Sodiumglycocholate and Sodiumglytaurocholate
32
Who synthesises bile salts
Cholesterol in the liver
33
Some bile salts in the duodenum get.... into.... for recycling in the ......
reabsorbed- blood- liver
34
The 3 locations of bicarbonate
Saliva- Bile- pancreatic juice
35
Bile duct empties into
duodenum
36
...... synthesises bile salts in the .......
cholesterol- hepatocytes
37
The function of the liver
Synthesises of bile salts, storage of glycogen and detoxification of alcohol.
38
The function of the large intestine
Absorbs nutrients and water and eliminates waste.
39
The method of absorption of Glucose/ galactose into the enterocytes
Co-transport with Na ions
40
The glucose into enterocytes carrier name
SGLUT-1
41
The method of diffusion of glucose out of the basolateral membrane ( epithelial cells) into the interstitial fluid
facilitated diffusion
42
The name of the channel protein letting glucose into the interstitial fluid out of the cell
GLUT-2
43
What's the point of actively transporting sodium out of the intestine epithelial cells?
Pumping Na through the Na/K pump helps in maintaining a Na ion concentration gradient between the and the epithelial cells. Therefore, allowing for the co-transport of Glucose/ galactose into the cells
44
Glucose/ Galactose absorption is highly dependent on
concentration of sodium ion
45
The method of diffusion of fructose out of the basolateral membrane ( epithelial cells) into the interstitial fluid
Facilitated diffusion
46
The Na+/K+ pump in the small intestine is only present in
The Na+/K+ is only in the inner plasma membrane
47
The method of absorption of Amino acids into the enterocytes
Active transport
48
The method of absorption of dipeptides into the enterocytes
co transport with H+
49
The method of absorption of short-chain fatty acids into the enterocytes
simple diffusion
50
The method of absorption of long-fatty acids and glycerol into the enterocytes
simple diffusion after being emulsified
51
Give account of the absorption of fats
Emulsification/ digestion/ formation of micelles/ simple diffusion/ reassembling into triglycerides/ packaged into chylomicrons/ simple diffusion→interstitial fluid→Lacteal
52
The salivation reflex is coordinated by
Medulla oblongata
53
The neural pathway for the secretion of gastric juice
stretch receptors→vagus nerve→brainstem→vagus nerve→gastrin into the blood
54
The triggers of the release of gastrin hormone
Vagus nerve, presence of food (Proteins)
55
The pancreatic juice secretion is mainly controlled by
the arrival of food at the duodenum
56
What causes the secretion of secretin
the stomach acid causes the release of secretin
57
The effect of releasing secreting
trigger the pancreas to increase bicarbonate amounts in the pancreatic juice before secreting it through main pancreatic duct
58
The presence of fat in the stomach trigger
triggers the release of the hormone enterogasterone
59
The effects of the enterogastrone
reduces gastric juices, slows the movement of the stomach, delays release of stomach content.
60
Define a balanced diet
a balance diet contains sufficient nutrients to maintain health and activity
61
Nutrients provide.... and ....
energy and materials
62
Nutrients provide energy and materials for ?
Growth, repair, movement and the functioning of organs
63
Define macronutrients with examples
nutrients required in large quantities. Proteins, fats and carbohydrates
64
Define micronutrients with examples
nutrients required in small quantities. minerals and vitamins
65
The meaning of essential nutrients and examples
nutrients that can be converted in the body but not made in the body. essential amino acids, essential fatty acids and most vitamins essential.
66
The role of water and fibre in peristalsis
water lubricates the digestive tract, fibre increase the bulk making the contractions more effective. Both water and fibre prevent constipation.
67
Malnutrition results from
an unbalanced diet ( Lack of nutrient or excess nutrients)
68
Individual dietary requirements influencing factors
Height/ weight/ gender/ age/ physical activity/ climate/ pregnancy or lactation/ fighting diseases
69
How come age influence the dietary requirements?
The younger the person the higher the metabolic activities within the body
70
The function of carbohydrates?
Provides energy
71
the function of lipids
Provides energy (Ketosis) and essential fatty acids for the plasma membranes and some hormones ( steroid hormones)
72
The function of proteins
provide essential amino acids for making structural proteins such as keratin. enzymes and antibodies. in starvation can be used for energy
73
The two types of vitamins are
Fat soluble and water soluble vitamins
74
Vitamin A function
Visual pigment and eye tissue formation
75
Vitamin D function
Hardening of the bone
76
Vitamin E function
Antioxidant ( protects against free radicals)
77
vitamin K function
A factor in effective blood clotting
78
Vitamin B
respiration, protein scythes, nucleic acids synthesis, nerve function
79
Vitamin C
antioxidant, collagene formation, and assist gut iron uptake
80
Functions of water in the human body
Solvent, hydrolysis, coolant and transport medium
81
Minerals for strengthening of bones and teeth
Ca and phosphorus
82
Mineral for muscle contraction
Ca
83
Mineral for ATP , DNA and RNA synthesis
phosphorus
84
Mineral part of haemoglobin and myoglobin
Iron
85
Vitamin that is important for iron absorption
C
86
Mineral that forms thyroid hormones
iodine
87
The minerals that conduct nerve impulses and muscle function
Na,K
88
The menials the maintain an osmotic balance
Na, Cl
89
The mineral in the stomach acid
Cl
90
The mineral responsible for the development of bones and teeth
Magnesium
91
mineral responsable for wound healing and insulin function
Zinc
92
Mineral that forms the enamel
fluoride
93
Energy consumption is calculated by ?
monitoring oxygen consumption
94
For every 1 dm3 of oxygen consumed how much energy will be made?
21.2Kj
95
The nutrition guideline intake that was used in the 50s onwards as recommendations for individuals
The recommended dietary allowance
96
The nutrition guideline that is more recent and applies to populations, taking into account that individual needs vary
The dietary reference values
97
What is the estimated average requirement
is the average requirement for a population ( 50% of the group will need less, 50% will need more)
98
What is the reference nutrient intake
Represents more than enough for most of the group
99
Lower reference nutrient intake is for
people with low needs
100
An example of a population that should use the lower reference intake
obese peple
101
Safe Intakes
recommendations set well below toxic levels. ex. for vitamin A and fluoride
102
Give reason reference nutrient intake of iron for adult females is greater than male adults
Due to the loss of blood in menstrual cycle
103
How many amino acids are there?
20
104
How many essential amino acids are there
8
105
how to get essential amino acids into your body?
diet ( animal proteins are rich in all essential amino acids
106
Wheat is deficient in what amino acid
Lysine
107
what amino acid is deficient in corn / maize
tryptophan
108
what amino acid is deficient in soya beans
methionine
109
Name the two essential fatty acids
Linoleic acid and linolenic acid
110
The DVR for fat intake is
33%-35% of total energy intake
111
The DVR for saturated fats is
no more than 10% of the total dietary energy
112
Sources of essential fatty acids
vegetable and fish oils
113
Why there is some increases in the DRV during pregnancy and lactation
Requirements change to support the growth of the uterus placenta and foetus
114
what's the point of taking folic acid during pregnancy ?
it protects against neural tube defects
115
Why is breast feeding healthy?
During the first few days the mom produce colostrum rich in antibodies
116
a cease where we have to increase the DVR
gut absorption disorders/ a patient on steroids
117
Why can not the wounds in scurvy patients heal?
Vitamin C is a cofactor in the enzymic synthesis of collagen. Without collagen no healing will happen.
118
Vitamin D as a hormone?
Vitamin D acts as a hormone stimulating the intestinal epithelial cells to absorb calcium
119
A shortage or complete lack of food
Starvation
120
People adapt to starvation by using
1-glycogen from the liver 2- fat stores 3- protein in muscle and other tissue
121
Starvation results in?
protein energy malnutrition
122
The two types of protein energy malnutrition are
kwashiorkor and marasmus
123
what happens in kwashiorkor
blood proteins are broken down to supply energy. Asa result blood moves from capillaries into the tissues causing hem to swell (oedema). Particularly of the liver
124
What happens in marasmus
reduction in size of the muscles
125
symptoms of anorexia nervosa
loss of body fat, thin hair, limited sexual development and cessation of the menstrual cycle
126
Obesity leads to
High blood pressure, high blood cholesterol, diabetes, coronary heart disease, cancer of colon, rectum, and prostate in men. and cancer of the uterus, cervix and breast in women.
127
Explain why women are at less risk of developing coronary heart disease
oestrogen and HRT protect women
128
Why is body mass is a risk factor for coronary heart disease
It increase the the cardio load and blood pressure
129
what diet increase the risk of getting coronary heart disease
A diet that is high in saturated fat and salt
130
Exercise can help with
controlling cholesterol levels, diabetes and obesity
131
Mention three risk factors of coronary heart disease
High blood pressure, High glucose levels and diabetes
132
what diet can decrease the risk factor of coronary heart disease
high in ant-oxidant vitamin B and E and high in fibre
133
explain why some of the lowest rates of heart diseases are found in countries with high fat intake
This might be bc the fats are unsaturated that will reduce the cholesterol levels
134
Why the consumption of vitamin E reduces the risk factor of a coronary heart disease ?
It is an anti oxidant and it protect the artery walls against atherosclerosis
135
Examples of degenerative heart and circulatory system diseases
coronary heart disease and stroke
136
what is atherosclerosis
the build up of cholesterol, fibres, dead muscle cells and platelets in the blood vessels
137
The layer of cholesterol blocking arteries
atheroma
138
High vs Low density lipoprotein
High transports cholesterol from the tissues to the liver. Low transport cholesterol from liver to tissues.
139
The causation of many coronary heart diseases?
Atherosclerosis in the left or right coronary arteries
140
The 3 forms of coronary heart diseases
Angina pectoralis, Heart attack, heart failure
141
What happens in Angina pectoralis
Severe pain due to shortage of blood to the heart muscle. No muscle death
142
what happens in a heart attack ?
sudden and severe chest pain due to the blockage of coronary arteries. part of the muscle dies due to the lack of oxygen
143
what happens in heart failure?
a blockage causes a gradual damage to the heart muscle. The heart weakens progressively
