chapter11 Flashcards
There still have macroevolution in modern human population
True
Macroevolution
Changes. In genes frequency influence human genetic and phenotypic variation
The difference between nature selection and others
Natural selection is about change allele frequencies relative to specific environment factor
But mutation,gene flow, genetic drift– infuence what alleles present in population
What happen when environment change
The selection pressure change Nature of the selection might change
The other called about allele frequencies shift
Adaptation
What is “height and weight “
Continues trait , it can shift
What is about Gaussian distribution
Selections for either tail
Bergmann’s rule
Warm areas, slender body type ( smaller - sized ) of its geographical range ;cooler areas more robust body type
Allen’s rule
Warmer area, protruding body parts( limbs ) longer; cooler area, shorter
The principle of Bergmann’s rule and allen’s rule
More/ less surface area to body mass= dissipation/ retention of body heat
The direction of natural selection is influenced by characteristics of the local environment
But not all change occurs as a result of natural selection
Environment influences also associat with ?
Genetic potential complex trait
Directional selection
Increasing the frequency of a trait ( positive favored or adaptive)
Normalizing selection
Removes harmful genes that arose by mutation Average value doesn’t change removes the extreme (against tail
How deal with normalizing selection
Medical interventions & improvements ( NICU,CS)= improved survival Relaxed selection
Relaxed selection
Is a selective phenomena. , selective pressure are either elimated or dramatically reduce
The difference of balancing selection and the other two
It is at genetic level
The feature balancing selection
Occurs when a heterozygous 杂合子（Aa) combination of alleles is positively favorited even though a homozygous 纯合子（aa AA) combination is disfavored
The benefit of balancing selection
The deleterious 有害的 allele ( morph 变形or form) can be deleted for MAINTAINED in population an individual only has 1 hope of the allele in GETEROZYGOTE
Acclimatization
Physiological adjustment in individual to environment condition ( impermanent physiological changes that people make when they encounter a new environment )
What is parasite
Bind red cells mature inside multiply until mature the. Break out RBCS
waste byproduct from the parasites spills out in the blood stream & fever ensues寄生虫副产品早起血液中 伴随发热
The function of red blood
Carry oxygen from lung , deliver via blood to organs and tissues of body
Carry carbon dioxide back to the lungs , via vein静脉 release expelled from body with exhale 呼
the circuit of duration 一圈
30-45 seconds
Which part creat red cell
Stem cell in the bone marrow 脊髓中干细胞
the life expectancy
120 days
What does red cell contains
Protein hemoglobin 蛋白质血红蛋白
What is the normal HB
HbA
What is the Point mutation
One of the DNA base pairs coding for hemoglobin production 碱基替换 插入或者缺失
the example of point mutation
Sickle cell HB ( HbS) 镰刀形细胞贫血
The name of sickle cell HB inherit feature
Mendelian principle
The rate of death and fitness of sickle cell disease
Death
The problem of sickle cell hemoglobin
Block blood flow & cause organ / tissue damage (+pain )
What does the Hbahbs look like
More RBCS with normal hemoglobin ,some RBCS with hemoglobin S
The relation heterozygote HbAHsbS and malaria
Does. Not have immunity of malaria
But a reduced severity of infection 不棉衣 但是可以降低严重性
the percentage if normal HbA and HBS in the RBCS
HbA 60% HbS 40 %
The life of RBCS with HbS
2-3 weeks 14-21 days
The action of HbS
It inhibit lifecycle
Reproduction of Malaria parasite in RBCS
Who is easy to get malaria
Children
What happen when HbAhba in a malarial environment
Mor e likely to die of malaria 在疟疾中死亡
what happen to HbA HbS in malarial environment
Protective benefits of HbS allele - selection allele
( overall lower frequencies of HbS allele. What happen to HbAHba
No selection adantage
Lower frequencies HbS allele. The Hbahbs
No selection advantage for HbS Frequencies lower
The form of HB
Two HbA ,HbS “ balanced polymorphism “ maintain two forms in polpulation
In the balance selection does the hererozygotes still have allele
Yeah HbAHbS
The true mean of advantage
Time & place specific ( environment )
About the revolution the macroevolution
Speciation
