Module 2 (part b) Flashcards
Amazon Molly
- Was the first vertebrate in which unisexuality was recognized.
- All individuals are females.
Parthenogenic Reproduction
Parthenogenesis occurs when females mate with, and receive sperm transfer from a male sailfin molly or a male shortfin molly.
(but there are no male mollies.)
Parthenogenesis
- In which the sperm do not fertilize the eggs, it only serves to activate the diploid eggs to develop
NOTE: All offspring produced are females that are clones (genetic copy) of their mother.
Parthenogenetic diploid species adult females are…
homozygous at all gene loci therefore all the progeny are also homozygous.
Apomixis (in plants)
Asexual reproduction within fertilization.
Sexual Reproduction Definition
Production of new individuals by joining of gamete to form a cell (zygote) by the process of fertilization.
Asexual Reproduction Advantage
- large number of offspring produced rapidly
- Only one individual required
Asexual Reproduction Disadvantage
- Limit or no genetic variation
Sexual reproduction of flowering plants…
-Self-fertilization
- Cross-fertilization ——> Pollination
Animals
- Cross Fertilization
Hermaphrodites Example
Earthworms and Planaria
Sequential Hermaphroditism
Some plants and animal species begin life as one sex, changing sometime to the other is a process called…
What does the loss of the dominant female prompts?
A sex change in her male partner and maturation of the most dominant immature fish as the new breeding male.
Sexual Reproduction
Production of new individuals by the exchange of genetic material form two individuals of different mating types.
Sexual Reproduction Advantage
- Increases genetic variation to new genotypes.
- Enhances reproductive success in changing environments
Sexual Reproduction Disadvantage
- Locate a mate
Conjugation
Two organisms fuse along a common surface and exchange genetic material (gene transfer ——> genetic variation).
- There are no increase in the number individuals.
Example; Paramecium
What does high genetic diversity means?
Greater ability of some individuals to survive in a changing environment.
Paramecium
- use both sexual and asexual reproduction
- Uses Binary Fission as asexual reproduction.
- Uses Conjugation as sexual reproduction.
Viruses
- consists of genetic material (nucleic acid, DNA, or RNA)
- Contained within a protective protein coat called a capsid.
- Do not contain all 4 biomolecule
- Do not have a cellular structure
- Unable to replicate outside of a living system
- Do not reproduce.
- They infect the cells of living organisms. “infectious agents” which cause disease.
Viroids
- Infectious particle of plants
- Do not have a cellular structure
- Depend upon enzymes of plant host for replication
- Lack proteins
- Consist of a small RNA molecule
- RNA of viroids do not code for any proteins
Prions
- Are non-living entities
- More simple than viruses
- Lack hereditary material (DNA or RNA)
- Do not have a cellular structure
- Infectious agent
(brain disorder)
Viruses, viroids and prions…
Are non-living entities and lack cellular structure.
Not capable of reproduction or “independent” metabolism.
Water
- Is the matrix of life.
- 60% body mass of most animals and 95% of some plants
- Maintains osmotic pressure in cells.
Hypertonic
External solution that has a high solute concentration and low water concentration.
Hypotonic
External solution that has a low solute concentration and high water concentration.
Isotonic
External solution that has the same solute concentration and same water concentration.
Water always moves form a _________ to __________.
Low salt concentration to high salt concentration.
Isotonic:-
Solute outside = Inside cell
NO CHANGE
Hypotonic:-
Lower Solute outside cell
CELLS RAPTURE AS WATER ENTERS
Hypertonic:-
Higher solute outside cell
CELL SHRINK AS WATER EXITS
Adaptation
Is the evolutionary process whereby a population becomes better suited to its habitat.
(Inherited characteristic of living organisms that enhances their chance of survival and reproduction in specific environments.)
Water and species
Each species is adapted to a set of environmental conditions dehydration - loss of body fluids below normal range.
What can be a significance cause of water loss?
Respiration
Main water source is by…
metabolizing fat stores
Counter-current exchange
Mechanism that minimizes water loss from respiratory system.
Heat:-
Moves from warmer to colder temperature
Inhalation
As an animal inhales. air from the environment passes across the nasal turbinate and it is warmed and moistened.
Exhalation
When animal exhales, warm water-saturated air from the lungs passes across the cool nasal turbinates.
Water stores in _______ then swallowed.
Sinuses
Surface areas…
of 1000 cm^2
Humans: 160-180 cm^2
Camel Adaptations
- Pads on the feet for walking on hot soft sand, toes spread out for better grip.
- Long strong legs for carrying load on back and keeping body further away from sand
- A hard fat layer of skin around stomach and thick leathery patches on knee protects camel from the extreme heat while seating on the sand.
- Long thick eye lids with double lashes reduce sand in eyes.
- Thick (tough) split lips to eat thorny desert plants.
- Hump: storage area for fat (food) supply in times of need
Camel Adaptation to avoid dehydration
- Metabolic water results to avoid dehydration.
- Thick fur insulates body against extremes of heat during the day and cold at night.
- Regulate their body temperature
(Camel do not sweat. Does not overheat that reduce water loss and energy.) - Can rehydrate very quickly (>200 liters in 3 minutes)
- can go for 2 weeks without drinking water.
- Extremely long intestine (colon) for reabsorbing water
- Concentrated urine (preventing water loss)
Camel Regulates body temperature
As environmental temperature increases, the camel can raise its body temperature, prevent sweating which prevents water loss.
Important:-
Air that is warmer than the body tends to heat an animal because heat always flows from a higher to a lower temperature.
