chapter 4 Flashcards
macro evolution
evolutionary relationships among higher species
micro evolution
changes in gene frequency
population
members of a single species occupying a particular area at the same time
gene pool
all of the alleles (DNA traits) in a population
p2
homozygous dominant 25%
2pq
heterozygous 50%
q2
homozygous recessive 25%
1
total population size
conditions to maintain a 1:2:1 gene frequency
no mutations, no genetic drift, no gene flow, random mating, no selection
how does one change the 1:2:1 gene frequency
mutations, genetic drift, gene flow, non-random mating, natural selection
differential reproduction
organisms with the best adaptations are most likely to survive & reproduce
stabilizing selection
selects for the heterozygous & selects against homozygous dominant & recessive (gene frequency is 0:4:0)
directional selection
selects against heterozygous and selects either homozygous dominant (4:0:0) or recessive (0:0:4)
disruptive selection
selects for both homozygous & against heterozygous (2:0:2)
allopatric speciation
require the presence of a physical barrier (the physical barrier reduces genetic flow)
sympatric speciation
does not require the presence of a physical barrier; reproductive isolating mechanisms reduce interbreeding
speciation
development of a new species
predating isolating mechanisms
mechanisms that prevent mating between species
habitat isolation
organisms in the same area but different parts of that area
temporal isolation
when two species breed at different times of day, season or years
behavioral isolation
they are not attracted to each other
mechanical isolation
genitals may not be physically compatible
postmating isolation mechanisms
mechanisms that prevent the formation of vigorous, fertile hybrids between species
gamete isolation
even if they are physically compatible, an embryo will not form if the egg and sperm do not properly fuse
zygote mortality
even if the fertilization occurs, the offspring may not survive
hybrid sterility
if the zygote survive, it may not reproduce
f2 fitness
if hybrid is able to reproduce, its offspring may not survive
ecology
allows one to study the interactions of organisms with the environment
ecosystem
contains communities & non living things
biosphere
potion of the earths surface where living things exist
terrestrial biomes are characterized by
climate, vegetation & type of animals
estuaries
where rivers meet sea
ocean zones
intertidal, pelagic, benthic
intertidal zones
where land meets water
pelagic zones
open ocean
benthic zone
seafloor
population ecology
factors that influence a population size, growth rate of the population, density, & features of the population structure
population dynamics
focuses on the relationships that exist among the different species in a community
lag phase
the organism is adjusting to the environment; plenty of space & nutrients
log phase
exponential growth; space & nutrients will begin to decrease
stationary phase
carrying capacity of the land; population size does not increase or decrease. birth=death
population dependent growth factor
facts that affect population density include logistic growth & carrying capacity of land
population independent growth facor
population growth is limited by natural disasters
competition
two populations compete for the same resources
interspecific competition
competition between members of different species
intraspecific completion
competition between members of the same species
symbiotic relationship
the relationship between two species that live in close association with each other
parasitism
a relationship between two organisms of different species where one benefits & the other is harmed
commensalism
a relationship between two organisms in which one organism benefits & the other is unaffected
mutualism
a relationship between two species in which bot species benefit
basic body plan
the body can be divided in to different components-cavities, tissue types & systems
cavities
spaces within the body which contain organs or viscera
dorsal cavity
back or posterior body surface & divided into cranial & vertebral/spinal cavity
cranial cavity
hold the brain & vertebral/spinal cavity
ventral cavity
front or anterior & divided into thoracic/chest cavity & abdominopelvic cavity
abdominal cavity
contains stomach, intestines, spleen & liver & other organs
pelvic cavity
contains urinary bladder, reproductive organs & rectum
scrotal cavity
found only in males-contains the male reproductive organs
epithelial tissue
a body tissue that covers the surfaces of the body inside & out; responsible for secretions & absorption
squamous cell
irregular shape, flattened edges
cuboidal cell
cube shaped cells
columnar cell
column shaped cells
muscle tissue
composed of muscle fibers; most abundant tissue type
skeletal tissue
attached to bones by tendons; responsible for voluntary movements; striped or striated in appearance
cardiac tissue
forms the contractile tissue of the heart; striated in appearance; under involuntary contraction
smooth tissue
lack of stations, walls of digestive tract, urinary bladder, & arteries; involuntary control
nervous tissue
forms a communication & coordination within the body; main cell is a neuron
connective tissue
synthesizes the matrix; small amount of cells scattered through the matrix
loose connective tissue
most common, holds organs in place
adipose connective tissue
provides insulation for the body & contains fat
blood connective tissue
fluid extracellular matrix used to transport substances throughout the body
integumentary system
skin, primary defense against infection, largest system
skeletal system
support body structure & protects organs
muscular system
produces movement & body heat
nervous system
detect changes inside & outside the body
endocrine system
produces hormones which regulate body activity
digestive system
converts food into molecules that can be absorbed by cells
respiratory system
exchanges gases between air & blood
circulatory system
transports materials to & from cells; helps stabilize the internal pH & temp
lymphatic system (immune system)
defends the body against infection
urinary system
maintain the volume & composition of the internal environment; excretion of fluid & blood-bone waste
reproductive system
females: produce eggs
males: produce & transfer sperm
assimilation
using absorbed food for growth
chemical digestion
enzymes break down food into small molecules that the body can use
amylase
enzyme in saliva that breaks the chemical bonds in carbs
lipid digestion
begins in the stomach, completed in the small intestines
the gall bladder releases ___ to aid in lipid digestion
bile
lipid—->_____+3_____
glycerol & 3 fatty acids
protein digestion
starts in stomach & completed in small intestine
protease
enzyme that digests protein
zymogen
inactive form of an enzyme
organs of the alimentary canal
mouth, esophagus, stomach, small intestine, large intestine
salivary gland
secretes saliva for digestion of starch
fundus
enlarged posterior portion of stomach
body
central portion of the stomach
pylorus
narrow inferior portion of stomach (bottom)
function of stomach
regulation of a slow, controlled emptying of food into the intestine
parietal cells secrete
hydrochloric acid
chief cells secrete
pepsinogen
small intestines
chemical digestion and nutrient absorption; one inch in diameter & 20 feet long
duodenum
first 10 to 12 inches of the small intestine
jejunum
next 8 feet of small intestine
ileum
last 12 feet of small intestine
large intestine
reclaims water; 2 1/2 inches diameter & 5-6 feet long
cecum
first 2-3 inches of large intestine
colon
middle 5 feet of large intestine
rectum
last 7-8 inches of large intestine
liver
site of cholesterol synthesis & detoxify body
systemic circulation
carry blood away from the heart & body
pancreas
produces several enzymes, produce bicarbonate to neutralize the acidic gastric juices, make insulin which controls blood sugar levels
heart
composed of cardiac muscle tissue
right side of heart
handles oxygen poor or carbon dioxide rich blood (body)
left side of heart
handles only oxygen rich or carbon dioxide poor blood (lungs)
arteries
carry blood away from the heart
arterioles
small vessels that receive blood from the arteries
veins
blood vessels that carry blood back to the heart
venules
small vessels that gather blood from the capillaries into the veins
capillaries
where gas exchange occurs
pulmonary circulation
flow of blood from the heart to the lungs & back to the heart
where the heart is relaxed
diastole
when the heart contracts
systole
blood pressure
created by beating of the heart
blood pressure ranges between ___ systolic
110 & 140 mm Ha
blood pressure ranges between ___ diastolic
70-90 mm Ha
low blood pressure
systolic pressure of 100 or below
high blood pressure
hypertension; 140 mm Hg or higher
pulse
the rhythmic stretching go the Arties caused by the pressure of blood during contraction of ventricles in systole
composition of blood
55% plasma 45% formed elements
composition of plasma
90% water & 10% dissolved substances (salts, proteins, ions, hormones)
red blood cells
blood cells that carry oxygen from the lungs to the body cells
white blood cells
blood cells that perform the function of destroying disease causing microorganisms
platelets
blood clotting
