Adaptations for nutrition Flashcards

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1
Q

What is autotrophic nutrition

A

make own food from simple inorganic raw materials

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2
Q

What is photoautotrophic nutrition

A

use light energy to perform photosyntheis eg green plants , protoctista, some bacteria, autotrophic

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3
Q

What does chemoautotrophic mean

A

use energy from chemical reactions prokaryotes autotrophic

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4
Q

What does heterotrophic mean

A

consumes complex organic molecule produced from autotrophs

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5
Q

What does saprotrophic mean

A

feed on dead or decaying matter by secreting enzymes extracellularly and absorb products eg bread mould heterotrophs

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6
Q

What does parasitic nutrition mean

A
  • obtain nutrition form another living organisms called host over long periods of time whilst causing it harm
  • endoparasites live within hosts body eg tapeworm
  • extoparasites live on surface eg human head lice
  • heterotrophs
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7
Q

What does holozoic nutrition mean

A
  • form of nutrition used by most animals where ingest and digest food absorbing nutrients
  • possesses a specialised digestive system
  • herbivores (plant materials)
  • carnivores (animal material)
  • omnivores (plants and animal material)
  • detrivores
  • (dead or decaying matter)
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8
Q

Descrbie nutrition in unicellular organisms

A
  • protoctista such as amoaba are holozoic heterotrophs
  • absorb nutrients directly throguh cell membrane via diffusion , ingesting larger molecules via endocytosis
  • and fluids by pinocyotisis into food vacuoles
  • lysosomes fuse with vacuoles release digestive enzymes
  • nutrients are absorbed throguh membrane of food vacuole waste is ejected by exocytosis
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9
Q

Describe nutritionin multicellular organisms (hydra)

A
  • some larger organisms have a single body opening eg hydra
  • live in fresh water
  • tentacles paralyse prey and move into a hollow body cavity through mouth
  • protease and lipase enzymes digest food extracellularly products are absorbed before indigestivle remains egested back out through mouth
  • more developed organisms possess a tube gut ingest one end egesting the other most advances posess a specialised region
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10
Q

Describe the human digetive system

A
  • gut consists of a long hollow muscular tube through which food eases along by peristalsis
  • ingestion - taking in food via mouth brining it into contact with digestive surface
  • digestion - larger biological molecules hydrolysed to smaller molecules absorbed across cell membrane it starts wtih mechanical digestion in mouth involveing teeth breaks large food pieces into smaller pieces completed by enzymes
  • absorption - passage of nutrient molecules through wall of gut into blood
  • egestion - elimination of undigested material eg cellulose fibre
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11
Q

What is the structure of the gut wall

A
  • consiste of four layers
  • serosa
  • muscle
  • submucose
  • mucosa
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12
Q

describe what the serosa does in the gut wall

A
  • outermost layer consisting of tough connective tissue which protects the gut reducing friction from other abdominal organs
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13
Q

Describe what does the muscle does in the gut wall

A
  • two layer circular and longitudinal smooth muscle contract in coordinated fashion pushing food along by peristalsis
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14
Q

Describe what does the submucosa does in the gut wall

A
  • connective tissue containing blood and lymph vessels to take away absorbed products of digestion
  • nerves are present co ordinate muscular contractions
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15
Q

Describe what does the mucosa does in the gut wall

A
  • inermost layer lining gut secrete mucus lubrication and protection from enzymes
  • depend upon region secretes enzymes absorbs digested food and nutrients
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16
Q

What is digestion

A
  • different food groups subsequent absorption takes place in different parts of the gut
  • different enzymes digest different food groups
17
Q

How are carbohydrates digested

A
  • amylase hydrolyses starch to maltose then maltase hydrolyses maltose to glucose
  • sucrase hydroluses sucrose into glucose and fructose
  • lactase hydrolyses lactose to glucose and galactose
18
Q

How are proteins digested

A
  • digested into polypeptides, dipeptides eventually amino acids
  • enzyjmes are peptidases according to where vrean peptide bonds
  • from the end are exopeptidase
  • from the middle are endopeptidase
  • and dipeptide seperating a dipeptide
19
Q

How are fats broken down

A
  • emulsified by bile hydrolysed into fatty acids and glycerol
20
Q

How is the mouth involved in digestion

A
  • buccal cavity
  • where digestion begins
  • teetch mechanically digest food tongue mixes with saliva rolls into a bolus for swallowing
  • saliva contains enzyme amylase , mucus lubricates food
  • amylase initiates starch digestion
21
Q

How is the oesophagus involved in digestion

A
  • mucles contract moving food down towards the stomach via peristalsis
22
Q

How is the stomach involved in digestion

A
  • food is digested by muscular action from stomach walls and gastric juices whcih contains hydrochloric acid and pepsin
  • pepsin is an endopeptidase secreted in an inactive form of pepsinogen activated by H+ ions prevent pre digestion
  • acidic Ph 2 also kills bacteria
  • mucus is produced by goblet cells in gastric pits and lubricates foods and protects the lining
23
Q

Describe how the duodenum is involved in digestion

A
  • first part of small intestine recieveing secretions from liver and pancreas
  • bile contains bile salts neutralising acidic food from stomach and emulsifies fats
  • pancreatic juice alkaline due to sodium hydrogen carbonate
  • pacreatic juice is secreted by islet cells in pancreas entering duodenum via pancreatic duct
  • contains endopeptidases and trypsiongen which is inactive converted into active trypin by engerokinase
  • amylase and lipase
  • brunner’s glands at base of crypts produce alkaline secretions also neutralise acidic food from stomach
  • mucosa of small intestine is heavily folded froming villi
  • in duodenu, endopeptidases and exopeptidases are secreted by cells at tip of villi and peptidases that bond to epithelial cell complete digestion to amino acids
  • matlase , lactase , sucrase are bound to epithelial cells complete digestion of carbohydrates
24
Q

Describe the role of the ileum in digestion

A
  • second part of small intestine is responsible for the absorbtion of digested food
  • villi and microvilli greatly increase surface aerea for flew absorbtion by diffusion, facilitated diffusion , co transport and active transport and for action of membrane bound enzymes
  • glucose enters epithelial cells by co transport and active transport by facilitated diffusion into capillary of villus
  • amino acids enther by active traansport into epithelial cells and then by facilitated diffusion into capillary of villus
  • fatty acids and glycerol enter by epithelial cells via diffusion where recombine into triglycerides and enter lacteal of villus
  • in epithelial cells smooth endoplasmic reticulum highly developed to addidt this process
  • water absorbed by osmosis into epithelial cells into capillary of villus
  • water soluble bitamins absorbed directly into blood while fat soluble vitamin absorbed into lacteal by diffusion
25
Q

What is the role of the large intestines in digestion

A
  • small villi present and responsible dor absorbtion of water formation of faeces stored in the rectum until egested
  • mutualistic bacteria in colon responsible for production of vitamin K and folic acid
  • glucoe and amino acids and transported by hepatic portal vein to liver where they are processed
  • lactaksdrain into lymohatic systam drainns blood via thoraic duct right before subclavian vein
26
Q

What are the adaptations for carnivores

A
  • evolved sharp inciors to tear flesh pointed canines pierce flash kill prey specialised molars called carnisials shear flesh and bone
  • powerful jaw muscles move lower jaw vertically up and down and able to open jaws wide accomodate large prey
  • intestines relativley short main constituent in diet iss protein relativley easily digested
27
Q

What are ruminanats and their adaptations

A
  • include cows and sheppes highly modified oesophagus
  • grasss is chewed form a bolus known as cud swallowed enters rumen mixes with mutualitic cellulose digesting bacteria produce glucose from cellulose
  • glucose is anaerobically respired by bacteria producing organic acids carbon dioxide and methane as waster products
  • remaining grass passes to the reticulum where reforemd into cud which is regurgitated rechewed to increase surface area for action of bacterial cellulase before being swallowed again
  • cud passes to omasum where organic acids are absorbed into blood
  • finally material passe to abomaum (true stomach) where acid kills baceria and pepsin begins digestion of bacteria
  • water is absorbed in the large intersitines in a similar way as in humans
28
Q

How are herbivores adapted

A
  • interlocking molar teeth rough prescence sharp enaels ridges teetch worn down by abrasive plant material grow continuoulsy
  • jaw moves sidewaus aid grinding food
  • vegetative diet made of cell walls in plant tisues call cellulose
  • made og beta glucose into microfibrils make cellulose difficult to digest
  • incisors and cnine slice vegetation cropping it
  • lack incisors porsess a horny pad lower teetch cut against it
  • gap called diastema allow food to me mixed during chewing processes
29
Q

What are parasites and briefly explain tape worms

A
  • parasits live in (endoparasites) or on (ectoparasites) a host organisms causing harm
  • pork tapework has two hosts (host in which sexual reprpduction tales place in human) and pig is secondary host
  • btoh needed to fully complete parasites life cycle if eggs directly eaten by human than infected meat cysts that can form in the brain
30
Q

What are adpatations of the tape worm

A
  • suckers and hooks - attatchment to gut wall
  • thin and large surface area to volume ratio - maximise absorption of digested food
  • produce enzyme inhibitors - prevent digestion by host’s enzyme
  • thick cuticle - protect from host’s immune reposnses
  • male and female reproductive systems - allow reproduction without second tapeworm
  • produce vast number of eggs - incrases chance of finding another host
  • eggs have resistant shells - survive until eaten by secondary host
31
Q

How does the tape worm get it’s nutrients

A
  • not have a digestive system absorbs products of host’s digestion directly through cuticle
32
Q

What are head louse and how are they adapted to be parasites

A
  • ectoparasite
  • feed sucking blood from scalp of host
  • wingless insects only pass to new host via direct contact
  • they lay eggs attatch to hair
  • legs are adapted to be claw like to grip onto hair
  • lay eggs glued to base of hairs
33
Q

Parasitic nutrition

A

involves obtaining nutrients from a host organism over a long period of time casuing it harm in the process

34
Q

Peristalsis

A

the wave of coordinated contracttion and relaxation of smooth muscles in the gut

35
Q

Hydrolysis

A

reaction involving chemical addition of water to break bond formed during condensation

36
Q

Emulsification

A

large fat droplets broken into smaller droplets which increases the surface area for lipase action

37
Q

Carnassials

A

modified upper premolar and lower molar teeth found in carnivores that have a scissor like action for slicing bone and flesh

38
Q
A
39
Q
A