Variations Flashcards
What are variations?
“Differences observed within a species. “
What causes variations?
“Inherited characteristics or environmental effects (acquired characteristics). “
Are most features a blend?
“Yes
Are inherited variations passed on?
“Yes
How do inherited variations occur?
“New genetic combinations during sexual reproduction and mutations. “
Types of variation
“Morphological and physiological. “
Two categories of variations
“Continuous and discontinuous. “
Continuous variation definition
“Gradual transition between two extreme forms. “
Continuous variation example
“Height in humans (short to tall). “
Discontinuous variation definition
“Sharp differences between various forms. “
Discontinuous variation example
“Presence or absence of ear lobes. “
What causes discontinuous variations?
“Mutations. “
Morphology definition
“Form and structure of an organism. “
What does morphology determine?
“Physical appearance and helps identify individuals. “
Morphological features with variations
“Size
Size variations examples
“Length
What is a frequency distribution curve?
“A curve showing the distribution of a feature with continuous variation. “
What does a frequency distribution curve show for size?
“Most individuals in a medium range
Color variations in humans
“Skin
Color variations in animals
“Coat patterns (e.g.
Color variations in plants
“Leaves
What are fingerprints?
“Impressions of ridges on fingers and thumbs. “
Are fingerprints unique?
“Yes
Physiology definition
“Functions and activities of a living organism or its parts. “
Are physiological variations visible?
“No
Examples of physiological variations
“Behavior patterns
Behavior pattern variations
“Aggressive/non-aggressive
Factors influencing behavior
“Environment and inherited characteristics (hormones). “
Tongue rolling variation type
“Discontinuous. “
PTC tasting variation type
“Discontinuous. “
ABO blood groups
“A
What are antigens?
“Substances on the surface of red blood cells. “
What are antibodies?
“Substances in blood plasma. “
How to identify blood groups
“Mixing blood with anti-A and anti-B serum. “
What is agglutination?
“Clumping of red blood cells. “
Rhesus factor
“Another antigen on red blood cells. “
Rhesus positive (Rh+)
“Blood has the Rhesus factor. “
Rhesus negative (Rh-)
“Blood lacks the Rhesus factor. “
How to test for Rhesus factor
“Using anti-Rhesus serum. “
Applications of variation
“Crime detection
Use of fingerprints in crime detection
“Identification
DNA ‘fingerprints’ use
“Solve crimes by analyzing DNA patterns from body cells. “
DNA ‘fingerprints’ effectiveness
“Especially useful in identifying rapists
When is blood transfusion needed?
“After losing much blood (e.g.
What is important for successful blood transfusion?
“Compatibility between donor and recipient blood. “
What happens if blood is incompatible?
“Donor’s red blood cells clump in recipient’s vessels. “
Blood group A compatibility
“Can be given to A and AB recipients
What part of blood is crucial in transfusions?
“Antigens on donor’s red blood cells and antibodies in recipient’s plasma. “
Universal donors
“Group O people (no A or B antigens). “
Universal recipients
“Group AB people (no anti-a or anti-b antibodies). “
Paternity determination
“Using inherited variations (blood groups
What can blood group tests show?
“Whether a man could not be the father
More conclusive paternity test
“DNA fingerprints. “
What is adaptation?
“Process by which an organism becomes fitted to its environment. “
What are adaptations?
“Features that are changed or modified for survival and reproduction. “
Types of adaptations
“Structural
Necessity of adaptation
“Organisms must adapt to survive. “
Factors involved in adaptation
“Variation
Competition definition
“Interaction for a resource in short supply. “
Resources organisms compete for
“Food
Types of competition
“Direct and indirect. “
Direct competition
“Interference with a competitor’s ability to obtain a resource (e.g.
Indirect competition
“Unequal efficiency in obtaining a resource
Competition outcome
“Only a small number of offspring survive and reproduce. “
Survivors’ characteristics
“Features that help them compete successfully. “
Example of adaptation to drier climate
“Better root system and thicker cuticle in plants. “
Result of successful adaptation
“Better survival
Complexity of adaptation
“Often involves multiple simultaneous adaptations in different body parts. “
Survival value definition
“Helpful variations for survival in a given environment. “
Examples of variations with survival value in dry conditions
“Efficient water tapping and reduced water loss. “
Inherited variations and survival value
“Only inherited variations have survival value. “
Natural selection definition
“Better-adapted varieties are ‘selected’ by environmental pressures. “
Example of natural selection
“Drier climate favors plants with better water conservation. “
Natural selection duration
“A continuous process due to constant environmental change. “
Variations important in natural selection
“Variations with survival value and inherited. “
Levels of competition
“Interspecific (between different species) and intraspecific (within the same species). “
Intensity of competition
“Intraspecific competition is generally more intense. “
Competition’s role in succession
“Hardy colonizers are replaced by better competitors as conditions change. “
Climax community
“Established through competition under stable conditions. “
Adaptations origin
“Natural selection acting on inherited variations. “
Adaptations types
“Modifications in form
Adaptations examples
“Structural adaptations
Structural adaptations definition
“Adaptations in body parts for specific functions. “
Structural adaptations functions
“Obtaining food
Food acquisition adaptations
“Mouths and hands/feet adapted to diet (plant or animal). “
Bird adaptations for food
“Beaks and feet adapted for catching
Insect adaptations for food
“Mouthparts and legs modified for feeding/catching prey. “
Spiny anteater adaptations
“Spade-like claws for digging
Toad adaptations for food
“Long sticky tongue attached at the front
Insectivorous plants adaptations
“Trap and digest insects for nitrogen. “
Predator-prey relationship
“Most animals are either predators or prey. “
Prey adaptation categories
“Escape and defense adaptations. “
Escape adaptations example
“Camouflage (blending with surroundings). “
Camouflage mechanism
“Concealing coloration. “
Defense adaptations examples
“Physical defenses (armor
Physical defenses examples
“Hedgehog spines
Bird of prey beak and feet adaptations
“Strong hooked beak for tearing flesh
Weaver bird beak adaptation
“Strong short conical beak for picking and cracking seeds. “
Woodpecker beak and feet adaptations
“Strong narrow pointed beak for boring
Hummingbird beak adaptation
“Long slender curved beak for sucking nectar. “
Kingfisher beak adaptation
“Long beak with saw-like edges for catching fish. “
Pelican beak adaptation
“Pouched beak for catching fish. “
Duck beak and feet adaptations
“Flat grooved/ridged beak for scooping/sieving
Fowl beak and feet adaptations
“Short stout conical beak for picking seeds
Flamingo beak and feet adaptations
“Boomerang-shaped beak with slits for scooping/sieving
Mimicry definition
“Resemblance of one species to another.”
Mimicry purpose
“To deceive predators.”
Chemical defences definition
“Use of chemicals to deter predators.”
Chemical defences examples
“Foul taste/smell (millipedes)
Individual responses definition
“Actions by a single animal to escape predators.”
Individual responses examples
“Fleeing
Group responses definition
“Coordinated actions by a group to escape predators.”
Group responses examples
“Schooling (fish)
Adaptive coloration definition
“Use of color to aid survival.”
Types of adaptive coloration
“Concealing coloration
Concealing coloration purpose
“Blend with the environment to avoid detection.”
Warning coloration purpose
“Bright colors warn of danger (e.g.
Disruptive coloration purpose
“Patterns break up the outline
Mimicry types
“Batesian (harmless mimics harmful) and Müllerian (harmful resemble each other).”
Batesian mimicry example
“Harmless hoverflies resemble harmful wasps.”
Müllerian mimicry example
“Bees and wasps have similar colors/patterns.”
Behavioural adaptations definition
“Actions that help survival and reproduction.”
Behavioural adaptations examples
“Courtship
Courtship behavior purpose
“Attract a mate.”
Courtship behavior examples
“Visual displays
Mating behavior purpose
“Increase fertilization success.”
Mating behavior examples
“Copulation
Parental care purpose
“Increase offspring survival.”
Parental care examples
“Nest building
Migration purpose
“Move to better conditions.”
Migration examples
“Birds flying south for winter.”
Hibernation purpose
“Survive harsh conditions.”
Hibernation examples
“Bears sleeping through winter.”
