exam Flashcards
digestive system
- the process when large complex molecules are broken down into simple substances
- animals make energy using food and oxygen
teeth
carnivore - sharp ripping teeth - incisors, canines, premolars, molars herbivore - wide grinding teeth - premolars, molars omnivore - both kinds of teeth - incisors, canines, premolar, molar
herbivore and omnivore digestive system
- long digestive system
- harder to digest cellulose
- bacteria in the intestines help
carnivore digestive system
- short digestive system
- protein easier to digest then cellulose
ruminant
teeth - some have no upper incisors or canines
large foregut - stomach has 4 chambers (human,reticulum, omasium,abomasum)
- richer and regurgitate feed to soften it
- foregut fermented - very large stomach, small intestine
e.g. sheep and cows
non-ruminant
handgut fermenter - small stomach and large intestine/colon
simple digestive system - sharp incisors and no canines
- long gut with hind gut
e.g. horse, rabbit, human
carnivore
- organisms that kills and eats animals e.g. fox
herbivore
organism that eats living plants or parts of them
e.g. cow
omnivore
- organism that eats both plants and animals
e. g. humans
mechanical digestion
- when large pieces of food are broken down into smaller parts through chewing or muscular movement in the stomach. aim is to increase the surface area of food so it can be acted on by enzymes in chemical digestion
chemical digestion
- when enzymes break down complex substances into their simplest form
e. g. carbs - glucose
ruman
- the first and largest section of the stomach
- solid food is mixed and partially broken down
- the human contains millions of bacteria an other microbes that promote fermentation
poultry
beak - no teeth can’t chew
crop - stores food
gizzard - crushes food using grit stones
vent - one opening for waste and reproduction
main roles of digestive system
ingestion
digestion
absorption
egestion
ingestion and adaptations
- taking in of nutrients into mouth
adaptations - organism choosing suitable food for ingestion
- mouth parts that assist in feeding behaviors
- physical features that assist in catching food
e.g. cheetah - speed
digestion and adaptations
- chemical and mechanical breakdown of food into small molecules that can be absorbed
adaptations - structure/ shape and number of teeth
- structure of alimentary tract
- indicate the foods an animal can digest
absorption
- the taking up of digested molecules into the internal environment of the cells digestive tract
egestion
- the removal of waste food materials from the body
transport system of the body 4 main function CS
- transportation of water, oxygen, and carbon dioxide
- distribution of nutrients and removal of waste
- maintenance of body temperature
- circulation of hormones
animal transport
- size and shape of animals affects the way nutrients and gases are transported to/from cells
small organisms CS
- arthropods e.g. insects and snails
- open circulatory systems
- fluids circulating are not fully enclosed in blood vessels
- heart pops the lymph into large spaces and bathes the cells with nutrients and then re-enters the heart
small/flat animals CS
e.g. flat worms or jelly fish
habitat - aquatic or high moisture region
- environment moves materials past cells
large Sa: vol ratio therefore substances diffuse in and out of their bodies fast
- no heart blood vessels or blood
- limited by the need for a high moisture environment
large animals CS
- large and/or metabolically active organisms
- e.g. fish, birds and mammals
- aquatic or terrestrial environments
- closed circulation
- blood circulated inside a network of blood vessels
- muscular heart pumps blood through blood vessels under pressure
- 2,3,4 chambered heart
blood parts
plasma - fluid that transports gases and waste
red blood cells - carry oxygen from the lungs to other body regions
white blood cells - to protect the body abasing foreign substances entering the body
platelets - fragments of cells that work to reduce blood loss by forming clots in the case of injury
fish CS
- 2 chambered heart (atrium and ventricle)
- closed circulation
- single circulation
amphibians CS
- 3 chambered heart
- left atrium, right atrium and ventricle
- double circulation
4 chambers, 2 halves - right and left side
- double circulation
- right side of the heart pumps blood to the lungs
- blood returns to the left side and piped to the rest of the body
- each side has 2 chambers (atrium and ventricle)
open vs closed system
define O - heart pumps into open cavity, quick way to transport nutrients around the body, less efficient C - heart pumps into network of vessels, more efficient, longer slower process, costs lots of energy heart O - more then one C - 1 vessels O - none or few C - elaborate network pressure O - low pressure, slow movement C - high pressure, fast movement
arteries
- carry blood away from the heart
- blood under great pressure
- thick, more muscular walls
veins
- carry blood to the heart
- blood under less pressure
- thinner walls, less muscular
capillaries
- move blood between veins and arteries and cells
- low pressure
- thin walls 1 cell thick
- huge surface area for exchange
gas exchange
- process by which the gases oxygen and carbon dioxide are exchanged between cells of an organism and the environment
- occurs by diffusion across a plasma membrane
breathing
- in order to extract oxygen from the air by the alveolus, air must enter the gas exchange area of the body and diffuse into cells
- air is moved in and out of the lungs by movement of the ribs and the diaphragm
- diffusion difference for oxygen traveling for the alveolus to red blood cells is very short
why do fish suffocate
- when out of water fish gill filaments stick togehter
- redoing SA of gills
- gases are not exchanged as when in water
- not enough O2 supply or CO2 removed
- poisoned by low pH enzymes reduce function
exchange across whole body surface
- small animals only
- large surface area to volume ratio
- body shapes are long and thin
e. g. earth worms and jelly fish
exchange across external gills
- gills can be damaged due to their delicate structure
exchange across internal gills
- water pass over the gills must be actively moving to maintain concentration gradient
- gills are protected from damage by being housed inside the animal
bird lungs
- high demand for oxygen
- metabolism is high and flight requires a lot of oxygen
- very efficient gas exchange system
- have air sacs to enable one way flow through lungs
bird lungs efficiency
large surface area - many tiny air capillaries
diffusion - short, thin walls
moist - air capillaries are wet
- conserve moisture
maintaining concentration gradient - air flows in one direction through the lungs regardless of inhaling or exhaling
exchange at the end of fine tubes through the body
- air diffuses through a tubular network
- spiracles
- insects breathe through spiracles allowing oxygen to travel along a network of tubes to reach their cells
mammal lungs and structure
- most efficient form of gas exchange
- trachea, bronchi, bronchioles, alveoli, diaphragm
mammal lungs efficiency
large surface area - many small alveoli
diffusion - short thin capillary walls
moist - wet lining
maintaining concentration gradient - air is exhaled and replaced with fresh inhaled air
- blood returns to heart to get pumped around the body
water use in plants
- keep cool
- photosynthesis and supports other chemical reactions
- keeps cells firm and supported
- transport minerals up
- it is absorbed through hypertonic root hairs
- then transported up the stem
- lost by transpiration from leaves
root hairs
- long very thin
- increase SA;vol ratio
- hypertonic so osmosis moves water into the roots
vascular bundle
xylem phloem and cambium
xylem
- carries water and minerals up from the roots
- via capillary action
- wide hollow pipes
phloem
- carries sucrose up and down from the leaves
- companion cells and sieve cells are living
- narrow
- water from the xylem moves into phloem via osmosis
cambium
- divides xylem and phloem
- making stem thicker and stronger
transpiration
water evaporates from leaves while stomata are open for the exchange of CO2 and O2 during photosynthesis
transpiration light intensity
- more light increase transpiration stimulates guard cells to take in water and open to allow CO2 to diffuse in for photosynthesis
temperature transpiration
- hotter increase diffusion and transpiration water evaporates quicker
humidity transpiration
high humidity reduces tranpsiration
- the surrounding air is dry diffusion of water is faster
- increasing diffusion gradient increases water loss
soil water transpiration
- wet soil increases transpiration
- plants can’t keep transpiring rapidly if water lost is not replaced
translocation
- transport of sugars and amino acids to all parts of the plant this is rapid and requires energy
- sucrose is actively pumped from photosynthetic cells into sieve cells
- energy for this is from companion cells
adhesion
water rises in the narrow vessels partly because water molecules are attached to the walls
cohesion
water moclules are attracted to each other and as water evaporates from the leaves columns of water are drawn up through the xylem
ring barking trees
- removal of a strip of bark from circumference of tree
- woody plants have vascular bundles in outer ring
- removes phloem
- sugars can’t be carried down to roots
- roots die due to lack of energy from respiration
water moevement in plants
- water enters hypertonic root hairs by osmosis
- moves into xylem in the center of the root
- moves up xylem
- leaves xylem into leaf by moving into spongy layer by osmosis
- water evaporates into the spaces behind the stomata and diffuse into the air
leaf structure
cuticle upper epidermis palisades layer spongy layer lower epidermis
upper epidermis
layers of cells covered by waxy cuticle prevents water loss
palisade layer
contain chloroplast at top for maximum light absorption
spongy layer
provides a spot for gas exchange large spaces for air and water vapour
- includes xylem and phloem
stomata include advantages and disadvantages
- opening between 2 guard cells
- allow for gas exchange or water and carbon dioxide
open ad - allow CO2 in
open dis - loose water
closed ad - restores the water inside the leaf
closed dis - respiration and photosynthesis wouldn’t occur - stomata close when guard cells loose water
guard cells
open and close stomata control transpiration
xerophytes
live in desert where water is sacred and evaporation is rapid
leaf adaptation xerophytes
waxy cuticle - reduces evaporation water proof
small, shed leaves - store water, less SA for evaporation
sunken in stomata - keeps humid air in reduces diffusion
cell membrane
controls movement of materials into and out of the cell
membrane structure
- fluid mosaic model = double layer of phospholipids
- includes proteins, glycoproteins, glycolipids and cholesterol
proteins
- act as a carrier and receptor cites
- control the movement of specific molecules into and out of the cell
- include channel protein, carrier protein and receptor protein
glycoproteins
play an important role in cellular recognition and immune response
glycolipid
act as a receptor surface and stabilize the membrane
cholesterol
disturbs the close packing of the phospholipids and regulates membrane fluidity
channel protein
open - open all the time
closed - open and close under certain condition
- like a conveyer belt
receptor protein
lock and key model specific to certain substances
carrier protein
carries a molecule through the membrane protein changes shape
- suck in squeeze out mechanism