Please enable JavaScript.
Coggle requires JavaScript to display documents.
PLANTS AND ANIMALS (DEFINITIONS (Auxin a growth hormone produced in the…
PLANTS AND ANIMALS
DEFINITIONS
Auxin a growth hormone produced in the cells of the apical meristem (tips of roots and shoots). Its job is to regulate plant growth. High concentrations in roots inhibits cell elongation, while high concentrations in shoots stimulates cell elongation.
Photosynthesis the process carried out by plant cells containing chlorophyll to produce energy in the form of glucose.
-
Nastic Responses rapid and reversible responses of plants to stimuli that do not come from any particular direction.
-
-
Kinesis random, non directional movement due to the presence of a stimulus. The rate of activity is determined by the intensity of the stimulus, not direction.
-
-
-
-
-
-
-
Circadian daily rhythms of the earths day/night cycle, caused by the earth rotating on its axis. These have a free running period of 24 hours.
Circalunar biological rhythms that correspond with the moons lunar phases. These have a free running period of 29.5 days.
Circaannual biological rhythms that correspond with the time fo the year. These have a free running period of 365 days.
Migration mass movement of a group of animals over a long distance for a specific purpose. The movement usually involves a return journey and us regulated by internal clocks in response to environmental cues.
Homing the ability of an animal to return to its home site after travelling away from it to find food or mates.
-
-
Photoperiod the amount of hours of sunlight in a day which plants and animals use to know seasons and migration times.
Photoperiodism any physiological response to changes in the photoperiod (hours of sunlight in a day) such as flowering.
Phytochrome a light sensitive protein that plants use to measure photoperiod. It exists in 2 forms, phytochrome red (Pr) and phytochrome far red (Pfr)
-
ANIMAL BEHAVIOURS
-
HIERARCHIES
Hierarchies are the linear ranking from most dominant to most subordinate in order to establish an orderly access to resources. Hierarchy is determined through fighting and the strongest , most dominant animal is the alpha males, which has the first choice of food, mates and decides when the group will move.
TERRITORIES
Territories are established areas for feeding, mating and rearing the young which is marked and defended. Animals hold territories through aggressive behaviours.
-
-
REPRODUCTIVE BEHAVIOURS
There are 4 basic types of mating systems, each is differentiated by the genders of sexual partners.
POLYGYNY
Where a male mates with multiple females, but each female only mates with a single male. Generally the female will provide the majority of care, leaving the male free to seek further mates.
Benefits:
-males have a very high chance of reproductive success as they dont contribute to offspring care so can seek mating opportunites instead.
Disadvantages:
-reduced genetic diversity since one male fathers so many young. This also leads to a higher chance of inbreeding and the passing on of genetic disorders.
POLYANDRY
Where one female mates with many males. The male will then stay behind and care for he offspring while the female moves on to find new mates.
Benefits:
-males care for and feed offspring while the females seek further mating opportunities, therefore achieving greater reproductive success in a season.
Disadvantages:
-this may lead to reduced genetic diversity since so many young share a mother. This could mean inbreeding and the occurrence of recessive traits and disorders showing up more often.
MONOGAMY
Where an individual has only one partner during their lifetime. The share offspring care responsibilities.
Benefits:
-in habitats where resources and mates are scarce, they will always have their mate.
-no energy is required to compete for a mate.
-in offspring requiring high care levels, the responsibility is shared so there is a greater chance of offspring and parents surviving.
Disadvantages:
-if one mate dies, the other will have low reproductive success in sebsequent seasons.
POLYGYNANDRY
When multiple males mate with multiple females. The offspring are then shared and cared for by the whole group.
Benefits:
-greater genetic diversity for the group
-less need for males to compete with eachother
-greater protection and care for the young
Disadvantages:
-the lack of a clear pair bond means that the females may not receive strong support in the caring for and raising of offspring.
-
BIOLOGICAL RHYTHMS
Biological rhythms are any cyclic change in a function or the levels of a bodily chemical. These rhythms can b e endogenous (internally) controlled by the internal biological clock, or be exogenous, (externally) controlled by synchronising internal cycles with external stimuli called zeitgebers.