StudyXY
RegisterLog in
Back to AI Flashcard MakerBiology /Biology IB HL - 10.3 Speciation Part 4

Biology IB HL - 10.3 Speciation Part 4

Biology20 CardsCreated about 1 month ago

This deck covers key concepts related to speciation, polyploidy, and evolutionary models in biology, focusing on the Biology IB HL curriculum.

PrintEmbedImportReport

What do two fertile polyploid offspring require in terms of parents? What is an exception?

Fertile polyploid offspring will typically require two polyploid parents (unless allopolyploidy occurs)
Tap or swipe ↕ to flip
Swipe ←→Navigate
1/20

Key Terms

Term
Definition
What do two fertile polyploid offspring require in terms of parents? What is an exception?
Fertile polyploid offspring will typically require two polyploid parents (unless allopolyploidy occurs)
Why do fertile polyploids need parents that are also polyploid?
This is because reproduction with the original parent population results in offspring with an uneven number of chromosome sets
Give an example of why polyploid parents are needed for fertile offspring
Example: diploid gamete + haploid gamete = infertile triploid zygote (cannot halve an uneven number when forming gametes)
In what species is polyploidy more common and why?
Consequently, polyploidy is far more common in plant species as they may lack separate sexes or can reproduce asexually
What is self-pollination?
Self-pollination – many plant species possess both male and female reproductive parts (monoecious) and can hence self fertilise
Why is asexual reproduction useful for polyploidy?
Asexual reproduction – infertile polyploids can still reproduce asexually via vegetative propagation
Log in to view all terms

Related Flashcard Decks

Biology

A-LEVEL PE (OCR): PAPER 3 - Ethics and Deviance in Sport

These flashcards describe key performance-enhancing methods, including blood doping—a technique used to increase red blood cell count and oxygen-carrying capacity, commonly by endurance athletes—and anabolic steroids, which boost strength, aggression, and training capacity. They highlight how these methods aim to enhance performance, often through artificial physiological manipulation.

21 cards
View Deck
Biology

A-LEVEL PE (OCR): PAPER 1 - Energy for Exercise

These flashcards cover fundamental concepts of cellular energy, including ATP as the primary energy source for muscular contraction, the role of the enzyme ATPase in ATP breakdown, and the definition of exothermic reactions that release energy. They provide a concise overview of how energy is produced and utilized in biological systems.

47 cards
View Deck
Biology

3MB Psychiatry: Neurobiology of Mood

This flashcard set explains the brain’s appetitive (approach) and aversive (defensive) mood systems, describing how they drive behaviour toward reward or avoidance of threat, and identifies the key neurotransmitters associated with each—dopamine for approach and serotonin for avoidance.

8 cards
View Deck
Biology

Psychology - Chapter 3 Biological Psychology Part 3

This deck covers key concepts from Chapter 3 of Biological Psychology, focusing on brain structures and their functions, including the occipital lobe, limbic system, brain stem, and nervous systems.

23 cards
View Deck
Biology

Psychology - Chapter 3 Biological Psychology Part 2

This flashcard deck covers key concepts from Chapter 3 of Biological Psychology, focusing on neurotransmitters, brain structures, and their functions.

25 cards
View Deck
Biology

Animal Behaviour - Applied Cat Ethology

In applied cat ethology, behavioural genetics are primarily inherited through the paternal line. This means certain behavioural traits, such as temperament or sociability, can be strongly influenced by the genetics of the sire (father).

56 cards
View Deck

Study Tips

  • Press F to enter focus mode for distraction-free studying
  • Review cards regularly to improve retention
  • Try to recall the answer before flipping the card
  • Share this deck with friends to study together
Biology IB HL - 10.3 Speciation Part 4
TermDefinition
What do two fertile polyploid offspring require in terms of parents? What is an exception?
Fertile polyploid offspring will typically require two polyploid parents (unless allopolyploidy occurs)
Why do fertile polyploids need parents that are also polyploid?
This is because reproduction with the original parent population results in offspring with an uneven number of chromosome sets
Give an example of why polyploid parents are needed for fertile offspring
Example: diploid gamete + haploid gamete = infertile triploid zygote (cannot halve an uneven number when forming gametes)
In what species is polyploidy more common and why?
Consequently, polyploidy is far more common in plant species as they may lack separate sexes or can reproduce asexually
What is self-pollination?
Self-pollination – many plant species possess both male and female reproductive parts (monoecious) and can hence self fertilise
Why is asexual reproduction useful for polyploidy?
Asexual reproduction – infertile polyploids can still reproduce asexually via vegetative propagation
Are polyploidy crops useful?
YES Polyploid crops may be particularly desirable to farmers
What are two reasons why polyploid crops may be desirable?
Allows for the production of seedless fruits (e.g. triploid watermelons are infertile and hence do not produce seeds) Polyploid crops will typically grow larger and demonstrate improved longevity and disease resistance (hybrid vigour)
Therefore what may farmers do to plants?
Consequently, farmers may induce polyploidy in certain plant species by treating plants with certain drugs (e.g. colchicine)
What is the genus allium composed of?
The genus Allium is comprised of monocotyledonous flowering plants and includes onions, garlic, chives and leeks
What has occurred in the genus Allium?
In many of these species polyploidy has occurred, resulting in reproductively isolated populations with distinct phenotypes
Give 3 examples of polyploidy in the genus Allium
Diploid (2n) = ~ 16 chromosomes (e.g. Allium cepa – garden onion) Triploid (3n) = ~ 24 chromosomes (e.g. Allium carinatum – keeled garlic) Tetraploid (4n) = ~ 32 chromosomes (e.g. Allium tuberosum – chinese chives)
In what ways may evolution occur?
Evolution occurs both within a species (microevolution) and across the species barrier (macroevolution = speciation)
Via what two methods may evolution via speciation occur?
Evolution via speciation may occur by one of two alternative models: phyletic gradualism or punctuated equilibrium
What does phyletic graduation suggest?
According to this model, speciation generally occurs uniformly, via the steady and gradual transformation of whole lineages
What type of process does phyletic gradualism suggest speciation is?
In this view, speciation is seen as a smooth and continuous process (big changes result from many cumulative small changes)
What evidence is there for phyletic gradualism?
This view is supported by the fossil record of the horse, with many intermediate forms connecting the ancestral species to the modern equivalent
What does punctuated equilibrium suggest?
According to this model, species remain stable for long periods before undergoing abrupt and rapid change (speciation)
What type of process does punctuated equilibrium suggest speciation is?
In this view, speciation is seen as a periodic process (big changes occur suddenly, followed by long periods of no change)
What evidence is there for punctuated equilibrium?
This view is supported by the general lack of transitional fossils for most species – however such absences could also be explained by the relatively rare and irregular conditions required for fossilisation