Lecture 16 Flashcards
(80 cards)
1
Q
Herbivores
A
eat autotrophs (plants)
2
Q
Carnivores
A
eat other animals
3
Q
Omnivores
A
eat plants and animals
4
Q
Suspension feeders
A
extract food particles suspended in surrounding water
5
Q
Substrate feeders
A
live within or atop their food source. eat their way through the food source (earth worms)
6
Q
Fluid feeders
A
suck nutrient rich fluids from their host. host can biplane or animal (mosquito)
7
Q
Bulk feeders
A
ingest large pieces of food, utilize utensils, claws, jaws, or teeth. kill prey
8
Q
4 stages of food processing
A
- ingestion
- digestion
- absorption
- elimination
9
Q
Ingestion
A
act of eating
10
Q
Digestion
A
breakdown of food into molecules small enough to be absorbed by body.
11
Q
Mechanical breakdown/digestion
A
occurs in the mouth of humans and other animals. teeth break food into smaller pieces increasing surface area.
12
Q
Enzymatic breakdown/digestion
A
enzymes breakdown the chemical structure of the molecules. occurs vie the addition of water
13
Q
Absorption
A
products of enzymatic digestion are absorbed into the cells lining the digestive tract. these products then enter blood stream and delivered to cells of the body
14
Q
Elimination
A
undigested material passes through the digestive tract
15
Q
Digestion occurs in ..
A
specialized compartments in order to avoid digestion of self tissues
16
Q
Food vacuole
A
smallest digestive compartment. fuses with lysosome.
17
Q
Most animals contain a internal compartment which..
A
permits extracellular digestion
18
Q
Gastrovascular cavity
A
digestive cavity with only one opening (mouth)
19
Q
Compartmentalized digestion
A
- gland cells lining the cavity secrete digestive enzymes
- enzymes break down soft prey tissue
- other cells present engulf small food particles
- food particles are broken down in food vacuoles
- undigested material is expelled though the mouth
20
Q
Alimentary canal has..
A
2 openings, mouth and anus.
21
Q
Alimentary canal contains..
A
- pharynx
- esophagus
- small intestine
- anus
22
Q
Esophagus
A
lead into a crop, gizzard or stomach. stomach/gizzard may temporarily store food. muscular. churn and grind food
23
Q
Small intestine
A
bulk of enzymatic digestion and all nutrient absorption occurs here
24
Q
Anus
A
undigested materials are expelled through the …anus
25
Earthworms as alimentary canals
food enters pharynx from mouth. passes through esophagus and stored in crop. gizzard contains sand and gravel and digests the food. digestion and subsequent absorption occurs in the intestine.
26
Grasshopper as alimentary canals
uses a crop to store food also. digestion occurs in mid gut region. gastric punches here increase SA for absorption. handgun is to absorb water and compact wastes.
27
Birds as alimentary canals
have 3 separate chambers: a crop, stomach and gizzard (filled with gravel to pulverize food). chemical digestion and absorption occur in small intestine
28
Human digestion
peristalsis propels food though the GI tract. alternating waves of smooth muscle contract and relaxation.
29
Sphincters
regulate passage of food into and out of stomach. cardiac and pyloric sphincter
30
Stomach
accordion like folds increase absorptive surface area. can stretch to accommodate up to 2L of food/liquid.
31
Stomach secretes gastric juices...
- composed of mucus, strong acid and enzymes
- hydrochloric acid breakdown of chemical bonds in food.
- kills most bacteria that entered w food
- pH = 2
- mucus protects stomach lining from harsh acidity
- CHl also converts certain enzymes into their active form
32
Hormonal control of digestion
- gastrin is released from stomach cells into the blood in response to food,
- circulates in the blood returning to the stomach to stimulate secretion of more gastric juice
33
Small intestine
remainder of digestion occurs here and absorption of nutrients. produces digestive enzymes which aid in digestion
34
Digestive enzymes used during digestion are synthesized by pancreas ..
pancreatic juice which is a mixture of digestive enzymes and bicarbonate
35
Digestive enzymes used during digestion are synthesized by liver
produced bile which contains salts that emulsify fats. bile is stored by the gall bladder until required in small intestine.
36
Absorptive surface is increased by..
villi (projections lined with microvilli) and extend into lumen of small intestine great increasing surface area. absorptive surface is approx. 300 m2. (size of a tennis court)
37
Liver located
between intestines and heart.
38
Hepatic portal vein receives ..
blood from capillaries of intestine and transports nutrients absorbed by in testiness to liver.
39
Main liver function
remove excess glucose from blood. convert to glycogen which is stored in the liver.
40
Liver produces..
lipoproteins that transport fats and cholesterol to the cells of the body.
41
Liver is involved in ..
detoxification and modification of substance absorbed by the GI tract (alcohol). then secreted by the kidneys into urine. produces bile and processes nitrogen wastes from protein breakdown forming urea.
42
Large intestine
1.5 m long. outpocketings include blind pouch called the caecum and appendix.
43
Main function of large intestine
absorb remaining water. waste products are referred to as feces which are indigestible plant fibres and flora from the colon. (e.coli)
44
Carnivores have..
large expandable stomachs
45
Length of digestive tract
herbivores and omnivores have longer digestive tracts. vegetation is more difficult to digest so longer canal provides more time.
46
Herbivores usually have special chambers to..
house lots of bacteria to help animal by digesting cellulose into simple sugars
47
4 classes of essential nutrients
- essential fatty acids (linoleic acid to synthesize membrane)
- essential amino acids (8/20 can't be synthesized)
- vitamins
- mineral
48
Undernourishment
diet chronically deficient in calories
49
Malnourishment
long term absence of one or more essential nutrients
50
3 main phases of gas exchange
- breathing
- transport of gases
- bodily cells take up oxygen form the blood and release CO2
51
Breathing
exposes a large moist internal surface to air. oxygen diffuses across the cells lining the lung into surrounding blood vessels. carbon dioxide diffuses out of the blood into the lung
52
Transport of gases
oxygen that diffused into blood binds to hemoglobin in RBC. carbon dioxide transported in the blood from tissue to the lungs
53
Bodily cells take up oxygen from the blood and release CO2
oxygen is the terminal electron acceptor during cellular respiration in mitochondria
54
Respiratory surface
the location of gas exchange within animal. composed of living cells that must be kept moist to maintain function. gas exchange occurs but diffusion
55
Earthworms
entire outer skin surface used for gas exchange. no specialized organs. capillary layer immediately below the surface receives oxygen. must be damp/wet. usually small long and thin
56
Gills
extensions/ out folding of the body surface specialized for gas exchange. O diffuses across the gill surface into a capillary bed. carbon dioxide diffuses out of fish from capillary bed out of the gill. needs moist surface.
57
Tracheal system
respiratory system contained within animal. extensive system of branching internal tubes. respiratory system is at the tips of the tubes. gases are exchanged directly with body cells (no circulatory system)
58
Lungs
found in most terrestrial vertebrates. internal sacs lined with moist epithelium. large amount of branching internally. forms large respiratory surface. gases are moved between the lungs and body cells via circulatory system
59
Gill structure
4 gill arches on each side of the body. two rows of gill filaments project from each gill arch. each filament have many plate like structures called lamellae. which are the actual respiratory surfaces. and full of tiny capillaries so small that RBC must pass though single file
60
Ventilation of gills
water goes into mouth of fish and out side. may simply open mouth allowing water to flow. fish may also actively pump water across the gills by the opening closing of the mouth and opeculum.
61
Countercurrent exchange of gills
blood flows opposite the movement of water past the gills. transfer of material from fluid moving in one direction to a fluid moving in the opposite direction
62
Tracheal system
higher oxygen concentration in air and its very lightweight/less energy.
63
Trachae =
largest tubes open to outside of the animal. reinforced with chitin. engaged portions from air sacs near organs require high O supply
64
Tracheoles
smallest branches extending to every cell in animal body. tips are closed and contain fluid. gas is exchanged with body cells directly across surface. no circulatory system. insects alternately contact and reflex flight muscles to pump air rapidly though tracheal system
65
Mammalian lungs
located in thoracic cavity. separated by abdominal cavity by thick muscle called diaphragm.
66
Transport of air to trachea
air enters nostrils. filtered by cilia and warmed and humidified at is travels. moved through pharynx . epiglottis covers the trachea when swallow food in order to prevent choking. air travels through the larynx where vocal cords located. air travels down the trachea which is lined with cilia and thin mucus layer/ moist epithelial cells. cartilaginous rings keep trachea open
67
Transport of air from trachea to capillaries
passes through the bronchi. two brunch branch from the trachea and enter each lung. further branch into smaller tubules called bronchioles. they end in sacs called alveoli which are site of gas exchange. each alveolus is surround by a dense network of capillaries. oxygen diffuses across the alveolus into the capillary network. alveolus covered with a thin layer of surfactant decreases surface tension.
68
Oxygen enters the blood at..
the lung and carbon dioxide is subsequently unloaded. occurs by diffusion gases down their concentration gradient
69
Open circulatory system
found in invertebrates. fluid pumped through open ended vessels. follows out among cells. no distinction between blood and interstitial fluid. bodily movements help to circulate fruits throughout. fluid returns to the heart though several pores. pore has a valve to protect against backflow
70
Closed circulatory system
vertebrate system. called cardiovascular. blood confined to vessel and distinct from interstitial fluid.
71
3 types of vessels
- arteries: carry blood away from heart to body tissue
- veins: return blood to the heart
- capillaries: convey blood between arteries and veins at tissue level
72
Closed circulatory system of a fish
- - 2 chambered heart
- - Atrium receives blood from veins
- - Ventricle pumps blood to gills
- - After passing through gills large arteries carry oxygenated blood to the rest of the body
- - Arteries become arterioles which become capillaries which exchange material between blood and interstitial fluid
- - Capillaries become venules which become veins
73
Double circulation
after loosing pressure in the capillaries of the lung blood is pumped a second time.
74
Pulmonary circuit
carries blood between heart and lung tissues
75
Systemic circuit
carries blood between the heart and rest of body
76
Amphibians such as frogs have 3 chambered heart.
mixing of blood (oxygenated and deoxygenated occurs in the ventricle). some animals such as turtles and snakes have the venatical partially divided into minimize mixing
77
Birds and mammals have 4 chambered heart
- 2 atria
- 2 ventricles
- right side handles deoxygenated blood
- left side of heart handles oxygenated blood
78
Right ventricle
pumps deoxygenated blood into lungs via pulmonary arteries. blood flowing through the lung capillaries unloads carbon dioxide and picks up oxygen. oxygen rich blood returns to the heart via pulmonary veins into the left atrium which then flows into left ventricle
79
Left ventricle
this blood exits into systemic circulation via the aorta. aorta branched called coronary arteries which supply heart with blood. has branches to supply head, neck, arms and abdomen
80
In the tissues arteries lead into arterioles and then capillaries..
they then become venues and the veins. they then converge into inferior and superior vena cava which return deoxygenated blood to the right atria of the heart. blood then flows into the right ventricle and back into pulmonary circulation
