Bio Exam Iii

Front 1

Evolution

Back 1

gradual change in species to make them better suited (adapted) to their environment; descent with modification.

Front 2

Evolution requires two things

Back 2

1. Variation, which has to be heritable

2. Natural Selection

Front 3

Relative fitness

Back 3

the ability to produce fertile offspring and there by pass genes on

Front 4

Evidence for evolution

Back 4

1. The Fossil Record

2. Transitional forms in Fossil Record

3. Homology

4. DNA

5. Embryology

6. Vestigial Structures

Front 5

Homolgous vs Analogous structures

Back 5

Homology=Common ancestor

Analogous=Convergent evolution, not common ancestor

Front 6

Convergent vs Divergent Evolution

Back 6

Divergent=Had a common ancestor

Convergent=No common ancestor but similar characterisitics

Front 7

Phylogenetic Tree

Back 7

shows the evolutionary relatedness among species

Front 8

Microevolution

Back 8

change in allele frequencies change from generation to generation.

Front 9

Biological Species Concept

Back 9

a species is group of populations whose members can interbreed and produce fertile offspring

Front 10

Allopatric speciation

Back 10

appearance of new species due to geographic separation

Front 11

Sympatric speciation

Back 11

speciation without geographic isolation

Front 12

Hybrid polyploidy

Back 12

mostly happens in plants and gives rise to new species, which contain genes from two different species; most present-day plants are the result of hybrid polyploidy

Front 13

Steps of Hybrid Polyploidy

Back 13

1. A defect in fertilization leads to a union of haploid gametes from two different species

2. The resulting hybrid is haploid and sterile but most plants can reproduce asexually,which allows this hybrid to live and reproduce for an indefinite period of time

3. A later defect in cell division leads to DNA replication without segregation of sister chromatids. The result is a new diploid species capable of sexual reproduction.

Front 14

Nervous vs Endocrine Systems

Back 14

Nervous – rapid, short-lived response that depends on direct contact between cells (neurons).

Endocrine – slower, longer-lived signal; depends on circulation to deliver hormones.

Front 15

Hormones

Back 15

secreted by one organ in the body, travel through the blood and elicit a response at another site in the body

Front 16

Endocrine cell

Back 16

releases hormone

Front 17

Target cell

Back 17

responds to a hormone via a specific receptor

Front 18

Water-soluble hormones

Back 18

1. Proteins, peptides, modified amino acids

2. Cannot pass through the plasma membrane and therefore act on receptors (protein) on the surface of cells

3. Binding to cell-surface receptors initiates a process of signal transduction in the cells that both activates or inhibits proteins in the cell and changes gene expression (turns on or off genes)

Front 19

Lipid Soluble Hormones

Back 19

1. Steroids, secreted by sex organs or adrenal cortex, and thyroid hormones.

2. Pass through plasma membrane into cells

3. Bind to receptors (proteins) inside cell – nuclear receptors. Nuclear receptors are themselves transcription that, upon hormone binding, alter gene expression

4. Nuclear receptors not bound to hormone, may reside in the cytoplasm or the nucleus, but when activated (hormone binding)they act in the nucleus.

Front 20

Receptors

Back 20

1. Mediate a hormone’s action

2. Impart specificity to the system; hormones travel through the blood so all cells see them, but only cells with the right receptor will respond.

Front 21

hypothalamus

Back 21

the master endocrine regulator, releases hormones and inhibitory hormones that act on the pituitary

Front 22

Pituitary

Back 22

1. Posterior pituitary

2. Anterior pituitary

Front 23

Posterior pituitary

Back 23

– stores and releases oxytocin and anti-diuretic hormone (ADH)secreted by hypothalamus

Front 24

Anterior pituitary

Back 24

– responds to releasing and inhibitory hormones secreted by the hypothalamus

Front 25

Adrenal Gland

Back 25

1. Adrenal Medulla

2. Adrenal Cortex

Front 26

Adrenal Medulla

Back 26

– responds to neuronal input

a. Neuroendocrine cells respond to neuronal input by secreting hormone

b. Fight-or-Flight response – increases heart rate, blood pressure, and blood flow

Front 27

Adrenal Cortex

Back 27

– responds to ACTH from anterior pituitary

a. Mineral corticoids – regulate blood pressure

b. Glucocorticoids – raise plasma glucose,anti-inflammatory

Front 28

Thyroid Gland

Back 28

responds to TSH from anterior pituitary

Front 29

4 Types of Diabetes

Back 29

1. Type 1

2. Type 2

3. Monogenic

4. Gestational

Front 30

Type 1 and 2 Diabetes

Back 30

Type 1 diabetes: Autoimmune destruction of insulin-secreting βcells of the pancreas

Type 2 diabetes: Highly correlated with obesity. Two-hit disease involving defects in insulin secretion and action (insulin resistance)

Front 31

Monogenic and Gestational Diabetes

Back 31

Monogenic diabetes: Caused by a mutation in any one of ~24 genes. Generally dominant and generally involves a defect in insulin secretion (b-cell defect)

Gestational diabetes: Occurs in pregnant women as pregnancy is a period of natural insulin resistance, compensation is insufficient.

Front 32

Insulin

Back 32

the body’s chief anabolic hormone; it is generally involved in the uptake of nutrients and their conversion to storage forms

Front 33

Three Actions of Insulin

Back 33

1. Promotes the uptake of glucose by muscle cells,which then uses it for fuel or stores it as glycogen.

2. Promotes the utilization of glucose in liver,which synthesizes glycogen and fatty acids

3. Inhibits the breakdown of fat from adipose tissue.

Front 34

Insulin Secretion

Back 34

Beta cells of the pancreas secrete insulin inresponse to rising blood glucose levels

Front 35

Diabetes Treatment

Back 35

Type 1 diabetes is treated with insulinreplacement therapy; it requires injection ≥ 2x/day

Type 2 diabetes can be treated with diet andexercise; if and when that fails oral (pills) hypoglycemic agents are used andeventually insulin injection

Front 36

External Fertilization

Back 36

Happens in marine animals, both male and female gametes are released into the water where fertilization happens. Does not involve male-female physical contact and therefore depends on environmental cues.

Front 37

Internal Fertilization

Back 37

1. Almost all terrestrial animals

2. Sperm deposited in female reproductive tract 3. Requires copulation (intercourse, sex)

4. Requires complex reproductive systems

Front 38

Ovaries

Back 38

1. Follicles

2. Ovulation

3. corpus luteum

Front 39

Follicles

Back 39

produce eggs, estrogen

Front 40

Ovulation

Back 40

- Several hundred eggs released during the reproductive years, from puberty to menopause (12-50); ~1 every 28 days

Front 41

Corpus Luteum

Back 41

– formed from the remainder of the follicle; estrogen and progesterone

Front 42

Oviduct

Back 42

Fertilization and early embryonic development

Front 43

Uterus

Back 43

1. Endometrium – where embryo implants

2. Ectopic Pregnancy – implantation of the embryo anywhere other than the endometrium, usually in the fallopian tube (tubal pregnancy); serious and potentially fatal medical emergency

Front 44

Cervix

Back 44

1. Opening between uterus and vagina

2. Pap Smear – cells surrounding the cervix are removed and examined for cervical cancer

Front 45

Vagina

Back 45

Birth canal, entry point for sperm

Front 46

Vulva

Back 46

external genitalia, Labia, clitoris

Front 47

Testes

Back 47

1. Housed inside a scrotum

2. Sperm production (requires a lower temperature)

3. Testosterone production

Front 48

Epididymis

Back 48

1. Storage and further development of sperm

2. Ejaculation – expulsion of sperm

Front 49

Vas Deferens

Back 49

carries sperm

Front 50

Vasectomy

Back 50

(male sterilization, permanent birth control) – severing of vas deferens to prevent the delivery of sperm

Front 51

Urethra

Back 51

1. Carries semen or urine (not at the same time) 2. Semen – sperm cells (5% of semen, 200 – 500 million sperm/ejaculation) + fluids secreted from various glands.

Front 52

Penis

Back 52

erectile tissue

Front 53

Spermatogenesis

Back 53

Diploid cells in seminiferous tubules continuously divide (mitosis), so males produce sperm throughout their adult lives.

Front 54

Aquatic Biomes

Back 54

Marine and Freshwater

Front 55

Pelagic and Benthic Realm's

Back 55

Pelagic: Ocean/lake surface

Benthic: Ocean/lake floor

Front 56

Photic and Aphotic Zone

Back 56

Photic: Up to 200 meters, light is sufficient to support photosynthesis

Aphotic: 200 meters and below, not enough light to support photosynthesis

Front 57

Twilight and No Light Zone

Back 57

Twilight: some light but not enough for Photosynthesis

No Light Zone: complete darkness

Front 58

Land/Ocean Biomes

Back 58

Intertidal Zone

Estuary

Wetlands

Front 59

Freshwater Biomes

Back 59

Standing(lakes and ponds)

Running(streams and lakes)

Front 60

Terrestial Biomes

Back 60

Tropical Forest

Savannas

Deserts

Chaparral

Temperate Grasslands

Temperate Forests

Coniferous Forests

Tundra

Polar Ice