Adaptations for survival 1

Adaptations for survival 1
EL: To see what we already know
about adaptations and begin learning
about different types of adaptations
• Complete first column of the “Adaptations Biq
Questions” worksheet
• Put any other questions you have about
adaptations at the end
• Hand in when you are done (don’t keep it!!!) –
you’ll get it back at the end to see how much
you have learnt!
What is survival?
Organisms that are considered “successful” at
surviving in their environment:
1.Survive to reproductive age
1.Reproduce and have enough young to
ensure survival of the next generation
An adaptation is a feature that seems to equip an
organisms for survival in a particular habitat.
Adaptations can be structural, behavioural or
Examples of Adaptations
Type of Adaptation
Animal Example
Plant Example
Structural Adaptations
• Features of the shape and structure of the
organism that help it to survive in it’s
– Think of one example in an animal and one
example in a plant and write it down in your table.
Structural Adaptations
Behavioural Adaptations
• Behaviours undertaken by an organism that
help it to survive in it’s environment
• Think of one example in an animal and one example in a
plant and write it down in your table
Behavioural Adaptations
Physiological Adaptations
• Features of the organisms internal physiology
(e.g. body temperature, water balance, heart
rate, blood pressure ect) that help it to survive
in it’s environment
– Think of one example in an animal and one
example in a plant and write it down in your table
Physiological Adaptations
Page 291, qu 19, 22
Page 292, Biochallenge qu 5
Page 295 qu 11
Animal adaptations worksheet (to be handed
in next lesson)
• From completing the big questions, how
would you rate your pre-existing knowledge of
adaptations from 1 (terrible) to 10 (very
Adaptations for Survival 2:
EL: To begin learning about
physiological adaptations, focusing on
• Organisms cannot survive unless they are able
to control the internal environment of their
body, despite continual changes in their
• Homeostasis = The maintenance of a constant
internal environment despite changes in the
external environment.
What needs to be kept within narrow limits?
M.I.T.G.O.W.B + pH + wastes
Metabolites (eg blood glucose concentration)
Ions (eg salts)
Gases (eg CO2 and O2)
Osmolarity (ie water balance)
Wastes (e.g. urea)
Blood Pressure
Stimulus-response model
Transmission nerves
Transmission –
nerves or hormones
Stimulus-response model example
Negative Feedback
Increase in
blood CO2
Receptor in
arteries and
Transmission nerves
centre in
Negative feedback –
response counteracts the
More CO2
muscles in
Transmission nerves
Watch click view movie
• Individually or in groups of up to 4 people, use
the stimulus-response model to explain
homeostasis. You can do this by either:
– Performing a role play
– Writing and performing a song or rap
– Creating and performing an interpretive dance
– Creating a poster and presenting it to the class
– To be finished and presented next lesson
Reflection and Homework
• What have you learnt about homeostasis?
• Homework: Quick check qu: 1-4 pg 301
Adaptations for Survival 3:
EL: To demonstrate our understanding
of homeostasis and to learn about the
involvement of the nervous system
• Present your homeostasis piece to the class
The nervous system
• This communication system
controls and coordinates functions
throughout the body and responds
to internal and external stimuli.
• Maintains homeostasis by
detecting change and coordinating
the action of effector organs
• Responsible for unidirectional, fast
communication by electrical
The Central Nervous System (CNS)
 Consists
of the brain and spinal cord
Medulla Oblongata
Spinal Cord
The peripheral nervous system
• Nerves extending out to the
rest of the body from the
• Includes all sensory
neurons, motor neurons,
and sense organs
Nerve cells: Neurons
• The basic functional unit of the nervous
• Send impulses to and from the CNS and
PNS and the effectors (muscles/glands)
Nerve cells: Neurons
Soma/cell body
The control center of the
Directs impulses from the dendrites
to the axon
Control centre of the soma
Tells soma what to do
Highly branched extensions
of the cell body
Receive and then carry information
towards the cell body
Extension of the cell body
Carries information away from the
cell body
Myelin sheath
Insulating layer around axon
made of Schwann cells
Increases speed of impulse
Nodes of Ranvier
Gaps between Schwann
Saltatory conduction – i.e. speed of
an impulse is greatly increased by
the message ‘jumping’ the gaps
Gap between axon or one
neuron and dendrite of
Communication between nerve cells
Types of Neurons
• Receive
stimuli from
to CNS
• located near
organs (skin,
eyes, ears).
• Relay messages
between other
neurons such as
sensory and
motor neurons.
• Usually found in
brain and spinal
Effector/motor neuron:
• Carry impulses from
CNS to effectors to
initiate a response
• located near effector
(muscles and glands)
Types of Neurons
Fun Fact:
Where can the
largest cells in the
world be found?
The giraffe’s sensory and
motor neurons! Some
must bring impulses from
the bottom of their legs
to their spinal cord
several meters away!!
Types of receptors
Mechanoreceptors respond to
mechanicalenergy (e.g. ear drum)
Thermoreceptors respond to heat or cold (e.g.
nerve endings in skin)
Electromagnetic receptors respond to
electromagnetic energy (e.g. ampullae of
Lorenzini in sharks)
Photoreceptors respond to visible light and UV
radiation (e.g. eyes).
Chemoreceptors respond to chemical stimuli
(e.g. olfactory)
• Complete Quick check qu 5&6 pg 308
• Complete Chapter Review Question 3 on page
Reflection and homework
• How did the group activity help you to
understand homeostasis better?
• What did you learn about the nervous system
Homework: Complete any unfinished questions
Adaptations for Survival 4:
EL: To learn how the endocrine system
is involved in homeostasis, as well as
how animals regulate temperature
Endocrine System
• Uses chemical signals for cell to cell
• Coordinates the function of cells
• Response to an endocrine signal occurs within
minutes to hours
Endocrine System
Endocrine glands
Release hormones into the
Chemicals released in one part of
the body that travel through the
bloodstream and affect the
activities of cells in
other parts. body.
Endocrine system
Controlling Glucose levels
• Your cells need an exact level of glucose in the
• Excess glucose gets turned into glycogen in
the liver
• This is regulated by two hormones produces
by the pancreas: insulin and glucagon
If there is too
much glucose in
the blood,
insulin converts
some of it to
Glucose in the blood
If there is not
enough glucose
in the blood,
converts some
glycogen into
Glucose in the blood
• Complete quick check qu 7 pg 308
• Complete “Nerves and Senses” Worksheet
Detecting temperature change
• Most organisms have an optimal internal
and/or external temperature range
– E.g. Humans: internal temp approx 37oC
– E.g. coral: external temp approx 26oC
• Why? Optimal temperature for enzymes and
other internal processes. Above or below can
lead to lower functioning and possibly even
Detecting temperature change: Humans
• External temp change detected
by receptors in skin – one type
for detecting cooling, another
for heating
• Internal temp receptors found
deep within body – mostly
within brain, near spinal cord,
around large veins and in
digestive system
• Affector (sensory neurons)
relay the information to the
hypothalamus – the temp
control centre of the body
Maintaining core temperature
• Interaction of nervous and endocrine systems
• Maintenance requires heat gain balancing
heat loss – done in a number of ways
Losing heat
• Heat can be lost through radiation , conduction,
convection and evaporation
Losing heat
Losing heat
• Organism may also undertake
behaviours to lower
temperature, such as:
– Licking arms or legs to increase
evaporative cooling
– Increasing the amount of
surface area exposed
Gaining heat
• Hypothalamus initiates heat generation or reduction
of heat loss
• Heat can be generated through:
– muscle contractions converted to heat energy through
– metabolic heat generation involving the pituitary gland
• Heat loss can be reduced though:
– Constriction of blood flow to the skin (i.e. vasoconstriction)
– Piloerection of hairs on the skin
Gaining heat
• Organism may also undertake behaviours to
lower temperature, such as:
– Moving around (e.g. jumping up and down)
– Sheltering, putting on extra clothes, putting
heater on
– Huddling, reducing surface area exposed
Surface Area to Volume Ratio
• In a cold temperature surface area exposed to the cold air is
• On a very hot day, surface area is increased so that more
body heat is lost.
Cat on a hot day – flattens out in
a shady location, increasing its
SA:V ratio
Cat on a cold day – curls
up to reduce its SA:V ratio
Big or small?
• Do you think big or small animals stay warm
more easily? Write it down and why.
• Take a look at page 314 and see if you were
Animals adapted to the cold
• If the water in cells freezes, the cells are killed as ice
crystals pierce the plasma membrane.
• Pure water freezes at 0˚C, but cytosol with dissolved
materials in it has a lower freezing point, eg. Some salty
solutions freeze at -18˚C.
• Emperor penguins have number of adaptations to equip
them for survival in freezing conditions. These include:
Animals adapted to the cold
• A high metabolic rate - convert chemical energy in their food
into heat energy.
• This heat is retained by excellent insulation; layers of fat
underneath the skin and a thick covering of feather layers.
• They huddle together to reduce their surface areas exposed
to the cold wind.
• Circulation changes to slow heat loss through the feet.
• Counter current heat exchange in their flippers.
• Large body size to reduce SA:V ratio.
Ectothermic vs Endothermic
• Ectotherms: depend on external sources of
heat to generate body heat (what are some
• Endotherms: generate their own body heat
through internal chemical reactions
– Interesting fact: 80% of the energy mammals get
from their food is used to maintain core body
• quick check qu 8-12 on pg 317
• Biochallenge pg 336
• chapter review qu 2, 5, 7
• “Thermoregulation in mammals” worksheet
Reflection and homework
• What did you learn about thermoregulation
• Homework: Complete any unfinished
Adaptations for Survival 5:
EL: To demonstrate thermoregulation
• In groups of 3-4, complete activity 8.1 “The
skin and temperature control”
• Complete report INDIVIDUALLY on to sheet
and hand in
Reflection and homework
• What did this experiment confirm or
contradict about thermoregulation today?
Homework: Complete prac report
Physiological Adaptations for
Survival 6
EL: How aquatic animals and plants
Thermoregulation in aquatic
• Water is a much greater thermoconductor than air:
– i.e. heat is lost to water much faster than it is to the air
• However, aquatic mammals, such as whales,
dolphins and seals, are endothermic and breathe air
• In order to thermoregulate in water, aquatic
mammals have special adaptations that help them to
Thermoregulation in aquatic
1. Blubber: insulating layer of fat below the skin
and sometimes around internal organs. Can
be up to 50cm thick.
Thermoregulation in aquatic
2. Fur: Seal, sea lions and otters have a dense
(thick) layer of fur that traps a layer of air next
to the skin so that their skin never gets wet.
Thermoregulation in aquatic
3. Countercurrent exchange: Involves vascular
tissue in fins, flukes, tails and other
• An outgoing artery from the body carrying warm
blood transfers its heat to an incoming vein
carrying cold blood.
• This reduces amount of heat lost through skin
and ensures blood returning to the body is at the
right temperature
Thermoregulation in aquatic
Thermoregulation in plants
• Plants in a hot environment thermoregulate
– Radiating heat to the environment
– Transpiration of water - evaporative cooling (like
– Leaf shape – increasing leaf edge to surface area
Thermoregulation in plants cont…
– Protecting enzymes using heatshock proteins
– Leaves orientating themselves
away from the direct rays of the
sun (e.g. Eucalypts)
– Structural adaptations such as the
ability to hold water (e.g.
succulents, bottle trees)
– Reducing leaf surface area by
dropping leaves
• “Control of body temperature” worksheet
• quick check questions 13-18 on pg 322, & 1921 on pg 325
• chapter review questions 6&8 on pg 339
• What did you learn about thermoregulation in
aquatic mammals and plants today?
Homework: Complete any unfinished
Adaptations for Survival 7:
EL: To investigate how animals and
plants osmoregulate
Why osmoregulation is important
• Osmoregulation = maintenance of constant
internal salt and water concentrations in
internal fluids
• Controlling water balance is important to
ensure the cells of the body are in equilibrium
– Too much water outside cells and the cells will
absorb it, possibly exploding
– Too little water inside cells and the cells will
release water, possibly collapsing
Water balance in vertebrates
• Kidneys eliminate nitrogenous waste and
control water balance in all vertebrates
• The basic structure that filters nitrogenous
waste from blood is the loop of Henle .
• The differences in the length of the loop of
Henle are related to the
differences in need to
conserve water.
Water balance in vertebrates
• The longer the loop of Henle, the more water can
be reabsorbed into the bloodstream, and the
more concentrated their urine.
• Beaver – lives in fresh water, has a very short
loop of Henle and produces weak urine
compared to its body fluids.
• Kangaroo rat – lives in desert,
has a very long loop of Henle and
produces concentrated urine
compared to its body fluids.
Water balance and blood pressure
• As water balance varies, so too does blood
– Increased water = increased blood pressure (and
vice versa)
• Two major hormones involved are antidiuretic
hormone (ADHD or vasopressin) and renin
Desert animals
Abiotic factors in the desert environment include:
Low rainfall
Low humidity
High daytime temperatures
Low night temperature
Low soil moisture
Intense solar radiation
Organisms struggle to:
• Find free water
• Stay hydrated
• Keep cool
What behavioural changes would you need to make to
survive in the desert?
Camel adaptations
Camels can survive for several days without drinking water, even in
very high temperatures. They have several special features that
enable them to survive the extreme conditions they encounter in
the desert. These adaptations include:
A fluctuating core temperature, can be as low as 34˚C
& as high as 41˚C
Large roundish body, fat concentrated in the hump &
extremely thin legs
Can drink over 150L of water when available to
rehydrate quickly
A slower metabolic and breathing rate in summer
Blood with a high water content
Extremely dry faeces
Lying down for long periods during day
Urinating down its legs
Water wise – the spinifex hopping mouse
• It does not need to drink. The seeds, insects and roots that it eats
provide enough water to live on.
• It has no sweat glands.
• Its droppings are almost completely dry.
• Its kidneys waste very little water (its urine is one of the most
concentrated of any mammal).
• It is active at night (when it is cooler).
• It lives together in burrows (this
increases the humidity in the burrow and
reduces water loss).
• It even uses metabolic water efficiently.
• Mothers produce very concentrated milk
(and drink the urine of their young).
Water balance in plants
• Plants are 90-95% water
• Up to 98%of water absorbed by a plant is lost
through transpiration
• They cannot move around to search for water
Water balance in plants
• Features that help them to obtain and retain
water including
– Waterproof cuticle on leaves
– Sunken stomata
– Rolled up leaves
– Large vacuoles for water storage (eg cacti and
– Cylindrical leaves (e.g. hakea)
– No leaves (e.g. acacia)
• quick check qu 22-24 on pg 330
• quick check qu 25-30 on pg 335
• chapter review qu 9-15 on pg 338-40
Reflecton and homework
• What did you learn about osmoregulation in
animals AND plants today?
• Homework – finish activity 10.3 and any
Adaptations for Survival 7:
EL: To demonstrate water balance in
• “Water balance in animals” experiment
Reflection and Homework
• What did your experiment conclude about
osmoregulation in animals today?
Homework: Complete prac report
Adaptations for Survival 8:
EL: To explore innate behaviours
Starting to think about behaviours..
Abiotic factors in these polar environments include:
Freezing temperatures
Gale force winds
Variable sunlight with seasons
Organisms struggle to:
Stay warm
Ensure cells don’t freeze
Gather enough food
Avoid predation
Successfully rear offspring
What behavioural
changes would you need to make to survive in Antarctica?
• The study of animal behviour
• What are some behaviours that ethologists
might study?
What are innate behaviours?
• Behaviour that is essentially the same in all
members of a species and which can occur
without an individual having had prior
experience of the behaviour
• What are some human examples of innate
• What are some examples of innate behaviours
in other animals?
Development of innate behaviours
• Innate behaviours are not necessarily fully
developed at birth and may be modified by
– E.g. swimming and diving in Australian fur seal
– E.g. feeding in laughing gull chicks
Activity – simple innate behaviour
• With a partner, move out of direct light
• Look into your partner’s eyes and note down
the size of their pupil
• Shine a light into your partner’s eye BRIEFLY
and note down what happens
• Explain how this innate behaviour relates to
the function of the eye and why it is important
Innate vs learned behaviours
• Work in groups of 4. Each group will be assigned one
type of innate behaviour from pg 344-356 of the text
• In your group, you have 5 minutes to work out the
best way to demonstrate the behaviour to the rest of
the class in a way that helps them learn more about
it (i.e. hangman may not be your best option)
• You have a max of 3 minutes to present your
• Demonstrate simple innate behaviour
Reflection and homework
• What did you learn about innate behaviours
Homework: quick check qu 1-4 pg 357
Adaptations for Survival 10:
EL: To explore learned behaviours
Learned behaviours
• Behaviours that develop or change as a result
of experience
Innate vs learned behaviours
• Classical conditioning defined by Ivan Pavlov
– Learning through reward (or punishment!)
• Operant conditioning
– Learning through trial and error
• Response to a repeated stimulus gradually
• Why is this important in nature?
• So that animal isn’t wasting energy
responding to non-threatening stimulus
• Animal applies previous experience to the
solution of a new problem
• Rapid and irreversible learning occurring
during early stages of an animal’s life
• biochallenge on page 368
• quick check questions 5-8 pg 362
• chapter review qu 2-7 pg 369-372
Reflection and homework
• What did you learn about learned behaviours
• Homework: Complete unfinished questions
Adaptations for Survival 11:
EL: To learn about plant behaviour
Plant tropisms
• A plant growth response to an external stimulus
– Light = phototropism
– Gravity = geotropism
– Thigmotropism = touch
• Growth towards the stimulus is a positive tropism
• Growth away from the stimulus is a negative
• Responses rely upon chemical (endocrine) signals in
plant cells
What type of tropism is shown in these pictures?
Plant communication
Plant cells will send signals to one another to tell
1. When trees to drop their leaves.
2. When to start new growth.
3. When to cause fruit to ripen.
4. When to cause flowers to bloom.
5. When to cause seeds to sprout.
Leaf Drop
Corn Seeds
Plant hormones
• Plant cells produce
hormones that travel
throughout the plant
causing target cells to
• In plants, hormones
1. Plant growth &
2. Plant responses to
of hormone
Plant hormones
What causes plants to grow
toward light?
Phototropism experiments with
Involved in photo-and gravitropism
Stimulates cell elongation
Made in the shoot apex
Travels down the stem
Auxin promotes root growth
Other Effects of Auxin
• Apical dominance
• Prevents leaf abscission (ie leaf shedding)
• Enhances fruit growth
• Photoperiodism is a biological response to a change
in relative length of daylight and darkness as it
changes throughout the year.
• Phytochrome, and other chemicals not yet
identified, probably influence flowering and other
growth processes.
• "Long-day plants" flower in the spring as daylength
becomes longer (e.g. spinach).
• "Short-day plants" flower in late summer or early
autumn when daylength becomes shorter (e.g.
broad beans).
• "Day-neutral plants" flower when they are mature.
Reflection and homework
• What did you learn about plant behaviours
• Homework:
– quick check questions 9-13 pg 367
– Chapter review questions 8-10 pg 372
Adaptations for Survival 12:
EL: To explore reproductive strategies in
animals and plants
Type of reproduction
Gender system
Male and Female
Mode of fertilisation
Mating systems
(polygyny and polyandry)
And promiscuity
Breeding patterns
• Some animals have a set breeding/spawning/
mating season – ensures eggs and sperm
available at same time and that environmental
conditions are favourable
• Can be influenced by internal (i.e. hormones)
and external factors (i.e. temperature, day
Breeding patterns: Mammals
• Female mammals produce eggs during oestrus
cycle – length varies depending on species:
– 28 days in humans (more commonly called
menstrual cycle)
– 4-6 days on rats and mice
– one per year in wolves, foxes and bears
• Unlike humans, most mammalian females will
only accept mating during oestrus, when eggs
are released into the reproductive tract
Signs of oestrus
Number of offspring
• Quick and many: r-selection
– Reach sexual maturity early
– Produce large numbers of offspring and/or breed
more frequently (i.e. high fecundity)
– High mortality rates of offspring
– E.g. common octopus: 100,000-400,000 eggs!
Number of offspring
• Slower and fewer: K-selection
– Reach sexual maturity slowly and breed later
– Produce fewer and larger offspring (i.e. low
– Extensive parental care, lowering mortality rate
– E.g. humpback whales
Modes of offspring production
• Oviparity: Embryo/s develops externally in
eggs released by mother with nutrients from
egg yolk.
• Viviparity: embryo/s develop within mother’s
body and are born live.
– Egg yolk viviparity – e.g. grey nurse sharks
– Placental viviparity – e.g. placental mammals
– Marsupials – strange case!
Born to breed: The Antechinus
Flower structure
Flower structure
How do plants reproduce?
• Plants are sedentary, so need to transport
their reproductive cells (pollen) to the eggs of
another plant. How?
– Blown by wind
• what sort of flower would these have?
– Carried by an animal vectors (e.g. bees)
• what sort of flower would these have?
Pollen transfer
Wind pollinated
Vector pollinated
Dispersing offspring
• Embryo encased in a seed (sometimes found
in a fruit) that can be dispersed through:
– wind
– Water
– In or on animals
• Think, pair, share: What would be some
adaptations the seeds would need for each of
these dispersal methods?
Video: Private Life of Plants
Activity: Parental care
• Use the information provided and pg 388-390
in your text book to complete the “Parental
Care” worksheet
• Complete biochallenge (pg 401) with a partner
Reflection and homework
• What did you learn about reproductive
strategies in animals and plants today?
• Homework:
– quick check questions 1-25
– Chapter review questions 2-13 pg 402-404
Adaptations for Survival 17
EL: To apply our knowledge of
adaptations to Australian Fur Seals
• Visit
html and other websites on different species
of seals
• In pairs, Use the information to complete the
following table. You will need to share one
adaptation at the end of the lesson
Type of
survival by
Variation in
other seal
Reflection and homework
• How did looking in-depth at the Australian fur
seal help you to further understand
adaptations for survival?
• Homework: Study for adaptations test by
reviewing notes, completing concept maps
and finishing any unfinished chapter questions
Adaptations for Survival 18
EL: To test our understanding of
adaptations for survival
• How well do you think you did on your test
today? How could you improve your test
performance next time?
Adaptations for Survival
EL: To use our knowledge about habitats and
adaptations for survival to create a documentary
- By the end of this lesson, you will have decided on
your species of investigations and written a rough
timeline and plan
• Do you think your timeline and plan will allow
you to complete the assignment in time and
to a high quality? What letter grade are you
aiming for on this piece of work?
N.B. Please submit this reflection to me.