10.7-8 - Adaptations

Question 1

Define adaptation and state the 3 types.

Answer 1

Adaptation: features enabling the organism to survive in their habitat

• Anatomical - physical structur
• Physiological - body processes
• Behavioural - how an organism acts

Question 2

Give examples of anatomical adaptations

Answer 2

• Predators have sharp teeth to kill and chew prey
  
  • They also have a strong jaw to prevent dislocation when prey is struggling
• Camouflage to blend into its environment to hide from predators
• Body coverings - such as hair, scales, feathers and shell.
  
  • Helps organisms keep warm, shells provide protection
• Mimicry - copying another organims appearance or sound fools predators into thinking it is poisonous or dangerous

Question 3

Give examples of behavioural adaptations

Answer 3

• Seasonal behaviour
  
  • Migration - when environmental conditions are not favourable organisms leave, they return when they are favourable
  • Hibernation - period of inactivity slowing an organisms heart rate and breathing rate to reduce metabolic activity, so less food is required
• Plants open stomata in dry conditions to wilt the leaves, reducing SA of leaves exposed to sun reducing transpiration
• Some rabbits play dead if they think they have been seen

Question 4

Give examples of physiological behaviours

Answer 4

• Producing posion - e.g. reptiles producing venom, plants producing posion
• Some mammal kidneys extract water from urine to reduce the need to find or drink water
  
  • e.g. water holding frog
• Antibiotic production
  
  • Some bacteria produce antibiotics to kill other bacteria in surrounding areas

Question 5

What is convergent evolution?

Give an example

Answer 5

• Organisms from different taxonomic groups share similar anatomical features
  
  • They have analogous structures - features adapted to perform the same function but have different genetic origin

E.g. - Marsupial Mole & Placental Mole

• In a placental mole the placenta connects the embryo to the mother’s circulatory system in the uterus to nourish the embryo until it is mature at bith
• In a marsupial mole they leave and enter the marsupium (pouch) whilst still embryos
  
  • Complete development by suckling milk

Question 6

What is the mechanism of natural selection?

Answer 6

1. Organisms of a species have genetic variation, they are exposed to selection pressures
   
   • (factors affecting an organism’s chance of survival and reproductive success)
     
     • E.g. predation, competition, disease
2. Organisms with the best adapted characteristics will survive and reproduce, those least well-adaptated will die and not reproduce
3. Surviving organisms pass advantageous alleles and characteristics to offspring
4. Process repeated for many generation, increasing the proportion of organisms with the advantageous characteristics

Question 7

What are the implications of evolution?

Answer 7

Pesticide Resistance in Insects

• Pesticides kill susceptible insects, some insects have resistance
• They will reproduce and become more common with the resistive gene becoming more frequent in the gene pool
• Insects will damage crop

Antibiotic Resistance