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Biology Flashcards

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1
Q

Nucleolus

A

the site of production of rRNA transciption and processing. The size of the nucleolus is proportional to the amount of protein produced by the cell (more proteins, more ribosomes needed)

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2
Q

Rough endoplasmic reticulum

A

synthesizes all proteins (permits translation) that cross the membrane

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3
Q

Golgi body

A

source of transport tags for glycoproteins. Carbohydrates are necessary to produce the tags (glycosylation) needed for protein transport

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4
Q

Lysosomes

A

Contain enzymes that breakdown substrates, proteins (ex/ misfolded)

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5
Q

Peroxisomes

A

Responsible for the breakdown of long chain fatty acids by β-oxidation

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6
Q

Intermediate filaments

A

Proteins involved in cell-cell adhesion and integrity of the cytoskeleton

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7
Q

Obligate anaerobes

A

can not survive in an oxygen containing environment

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8
Q

Faculatative anaerobes

A

can use oxygen for aerobic metabolism if present or use anaerobic metabolism if it’s not

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9
Q

Aerotolerant anaerobes

A

unable to use oxygen but are not harmed by an oxygen environment

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10
Q

Gram negative bacteria

A

stains pink. Consist of thin peptidoglycan layer and outer membranes

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11
Q

Gram positive bacteria

A

stains dark purple. Consist of thick peptidoglycan layer

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12
Q

Episomes

A

A genetic element of bacteria that can replicate independently of the host

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13
Q

Virulence factors

A

traits that increase how pathogenic the bacteria is

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14
Q

Conjunction

A

Bacterial form of mating where a sex pili acts as a bridge for genetic material to cross. The transfer is unidirectional from the donor male (+) to the recipient female (-). Once the transfer is complete, the recipient (-) becomes a donor (+). Transfer between 2 donors (+) is not possible

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15
Q

Transduction

A

When a virus that carries genetic material from one bacteria to another through a vector

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16
Q

Transposons

A

Genetic elements that are capable of inserting and removing themselves from the genome

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17
Q

Lag phase

A

bacteria adapt to environment. Minimal growth occurs

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18
Q

Log (exponential) phase

A

bacteria adapt and grow exponentially

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19
Q

Stationary phase

A

Resources are limited and slows reproduction. The growth rate equals the death rate. The number of bacteria does not change

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20
Q

Death phase

A

resources are depleted

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21
Q

Virions

A

replicated progeny produced when a virus hijacks a host cell

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22
Q

Lytic cycle

A

Occurs when a virus begins to produce virions until the host cell lyses. Bacteria in the lytic phase are called virulent

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23
Q

Lysogenic cycle

A

Occurs when viral DNA is integrated in the host genome and is replicated

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24
Q

Prions

A

Infectious proteins that cause disease by triggering misfolding of other proteins

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25
Q

Interphase

A

consist of G1, S, and G2. Longest part of the cycle. DNA is in the form of chromatin

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26
Q

G₀ stage

A

when the cell is living and not doing anything to prepare for division. Occurs outside of G1

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27
Q

G₁ stage

A

Cells create organelles for energy and protein production. Cells must meet certain criteria like containing proper complement DNA

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28
Q

S stage

A

replication of genetic material. Chromosomes consist of identical chromatids (92 chromatids, still 46 chromosomes). Cells will now have double the DNA than G₁

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29
Q

G₂ stage

A

the cells checks to make sure DNA has been replicated correctly and if there is enough organelles and cytoplasm to divide

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30
Q

Telomeres

A

protective ends of chromosomes to protect DNA

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31
Q

Mitosis

A

when 2 identical daughter cells are created from a single cell. Occurs in somatic cells (non-sexual)

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32
Q

Prophase

A

The nuclear membrane dissolves and the nucleoli disappears. Chromatin condenses into chromosomes. Centrioles move to the edges of the cell and form spindle fibers

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33
Q

Kinetochores

A

serve as attachment points for kinetochore fibers in the center of centromeres

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34
Q

Metaphase

A

kinetochore fibers interact with spindle fibers and form the metaphase plate

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35
Q

Anaphase

A

sister chromatids are pulled apart when the kinetochore fibers are shortened

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36
Q

Telophase

A

Spindle fibers disappear. New nuclear membranes form around the chromatids

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37
Q

Meiosis

A

Gametocyte (germ cells) –> 4 non-identical gametes. It is 1 round of replication followed by 2 rounds of division

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38
Q

Meiosis I

A

reductional division and generates haploid daughter cells

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39
Q

Meiosis II

A

equational division and is similar to mitosis

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40
Q

Tetrad

A

a synaptic pair of 4 chromatids

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41
Q

Prophase I

A

Homologous pairs come together and intertwine in a process called synapsis. Crossing over occurs

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42
Q

Metaphase I

A

Tetrads align at the metaphase plate. Homologous pairs are lined up across from each other on the plate

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43
Q

Path of sperm

A

Seminiferous tubules —> epididymus —> vas deferens —> ejaculatory ducts —> nothing —> urethra —> penis
SEVE(N) UP

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44
Q

Seminipherous tubules

A

location of sperm production (spermatogenesis)

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45
Q

Spermatogonia

A

diploid stem cells

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46
Q

Leydig cells

A

secrete testosterone and androgens. Stimulated by LH

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47
Q

Sertoli cells

A

support cells. Stimulated by FSH. Secrete inhibin to feedback LH and FSH

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48
Q

Seminal vesicles

A

contribute fructose to nourish sperm

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49
Q

Ovaries

A

produce estrogen and progesterone

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50
Q

Primary oocytes

A

Formed during fetal development and have already undergone DNA replication. They are all diploid and arrested in prophase I

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51
Q

Secondary oocyte

A

arrested in metaphase II during ovulation unless triggered by fertilization

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52
Q

Fraternal (dixygotic) twins

A

form from fertilization of 2 eggs released during the ovulatory cycle

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53
Q

Identical (monozygotic) twins

A

form when a single zygote splits into two. If division is incomplete, conjoined twins can result

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54
Q

Stages of embryonic development

A

Zygote —> morula —> blastula —> gastrula —> neurula

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55
Q

Order of cell differentiation potency

A

Totipotent —> pluripotent —> multipotent —> non-potent

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56
Q

Ectoderm

A

Gives rise to integument, nervous system, and inner ear

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57
Q

Mesoderm

A

Develops into systems like the musculoskeletal, circulatory, and excretory. Also the gonads, adrenal cortex, connective tissue

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58
Q

Endoderm

A

Develops into epithelial linings of digestive and respiratory systems, pancreas, thyroid, bladder, and parts of liver

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59
Q

Selective transciption

A

only genes needed for a particular cell are transcribed and others are turned off

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60
Q

Induction

A

Ability of a group of cells to influence the fate of nearby cells by mediating chemical substances called inducers

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61
Q

Neural crest cells

A

Give rise to structures of the PNS

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62
Q

Brown fat

A

Releases more heat due to an insufficient ETC (due to an uncoupling protein). All infants generate heat due to inability to shiver. Contain multiple mitochondria

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63
Q

Teratogens

A

substances that interfere with early development. Ex/ alcohol, drugs, viruses, environmental chemicals

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64
Q

Autocrine

A

signals act on the same cell that secreted the signal

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65
Q

Paracrine

A

signals act on cells in a local area

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66
Q

Juxtacrine

A

signals stimulate receptors of an adjacent cell

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67
Q

Senescence

A

biological aging. At the cellular level this is due to shortened telomeres which results in the loss of genetic info

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68
Q

Foramen ovale

A

Connects R atrium and L atrium. This is important because it shunts blood away from the lungs and liver. The liver can not 1. Stand the high pressures and 2. Does not need the blood because it is not doing detoxification in the womb

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69
Q

Ductus arteriosus

A

shunts from pulmonary artery to aorta

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70
Q

Ductus venosus

A

Shunts from placenta via umbilical vein to IVC. This is important because this allows for max oxygenated blood to enter the heart

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71
Q

Gestational period

A

38 weeks (9 months, 280 days) from conception to birth. Gestation is measured from the last day of the menstrual period till birth (2 weeks before fertilization) = 40 weeks

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72
Q

Myelin

A

It increases the membrane resistance to ion leakage, allowing ions to travel farther. It decreases the capacitance of the axon when the thickness of myelin increases

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73
Q

Oligodendrocytes

A

produce myelin in the CNS

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74
Q

Schwann cells

A

produce myelin in the PNS

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75
Q

Synapse

A

nerve terminal, synaptic cleft, and post synaptic membrane

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76
Q

Astrocytes

A

nourish neurons and form the blood-brain barrier

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77
Q

Ependymal cells

A

Line the ventricles in the brain and produce CSF. Simple cuboidal

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78
Q

Microglia

A

phagocytic cells of the CNS

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79
Q

Ventral (anterior) root

A

efferent (motor) information

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80
Q

Dorsal (posterior) root

A

afferent (sensory) information

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81
Q

Spinal nerve

A

where the roots join before they divide into the rami. Sensory and motor

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82
Q

Anterior ramus

A

to the anterior component of the body, and the limbs

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83
Q

Posterior ramus

A

to the back (posture), skin

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84
Q

Layers of meninges

A

dura, arachnoid, pia

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85
Q

Subdural space

A

can become a potential space in a pathological situation (fluid can fill it). Ex/ subdural hematoma — blood collecting in this space

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86
Q

Subarachnoid space

A

contains the CSF

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87
Q

Extradural space

A

contains nerves, vessels, and fat. Location of epidural anesthesia injection

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88
Q

Resting membrane potential for neurons

A

-70 mV. The inside is (-) and the outside is (+)

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89
Q

Equilibrium potential of Na and K

A

-90 mV and 60 mV

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90
Q

Temporal summation

A

multiple signals are integrated during a relatively short period of time

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91
Q

Spatial summation

A

the additive effects are based on the number and location of the incoming signals

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92
Q

Absolute refractory period

A

no amount of stimulation can cause another AP to occur

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93
Q

Relative refractory period

A

a greater than normal stimulation can cause an AP because the membrane is starting from a potential that is more (-) than the RMP

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94
Q

Glutamate

A

excitatory NT that acts on the brain

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95
Q

GABA

A

inhibitory NT that acts on the brain

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96
Q

Asparate

A

excitatory NT that acts on the spinal cord

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97
Q

Glycine

A

inhibitory NT that acts on the spinal cord

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98
Q

Referred pain

A

Pain perceived at one location but it is not the site of the stimulus. Incoming signals from visceral and somatic afferents coming to the same spinal segment “confuse” the brain into thinking that the visceral pain is coming from elsewhere

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99
Q

Peptide hormones

A

Water soluble and travel through the blood. Short lived but effects are rapid. Charged and can’t pass through a membrane so they utilize the signaling cascade

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100
Q

Steroid hormones

A

Not water soluble and need carrier proteins. Lipid soluble and can easily cross the cell membrane (receptors are intracellular). Slower but are longer lived.

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101
Q

Tropic hormones

A

Hormones that stimulate an intermediate that secretes a hormone. Ex/ GnRH stimulates LH to release testosterone/estrogen from the gonads, CRF, TRH

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102
Q

Direct hormones

A

secreted and act on a target directly. Ex/ insulin

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103
Q

Anterior pituitary hormones

A

FSH, LH, ACTH, TSH, Prolactin, Endorphins, GH

FLAT PEG - flat are tropic, peg are direct

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104
Q

Prolactin

A

Stimulates milk release from mammary glands. Prolactin release is under the inhibitory control of dopamine release from the hypothalamus

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105
Q

Endorphins

A

decrease pain perception

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106
Q

Growth hormone

A

promotes growth of bone and muscle, and fatty acid breakdown (B oxidation)

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107
Q

ADH

A

Released from the posterior pituitary. Increases reabsorption of water from collecting duct of kidney. Low blood pressure, low blood volume (baroreceptors), or high plasma osmolarity (osmoreceptors) cause its release

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108
Q

Oxytocin

A

Released from the posterior pituitary. Stimulates uterine contractions during labor and contraction of smooth muscle in the breast during lactation. Has a positive feedback loop

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109
Q

Hypothyroidism

A

Thyroid hormones are not secreted in sufficient amounts. Leads to lethargy, decreased body temp, slow HR, and weight gain

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110
Q

Calcitonin

A

Decrease plasma Ca levels by increasing secretion from kidney, decreasing absorption in gut, and increasing storage in bone

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111
Q

Thyroid

A

sets the basal metabolic rate through T₃ and T₄, and controls calcium homeostasis through calcitonin

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112
Q

Parathyroid hormone

A

Activates vitamin D which is required to absorb Ca and phosphate in the gut

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113
Q

Glucocorticoids

A

Regulate glucose levels. High glucocorticoid levels –> increased insulin levels –> increased fat storage

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114
Q

Mineralocorticoids

A

regulate salt and water homeostasis

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115
Q

Aldosterone

A

mineralocorticoid that increases Na+ reabsorption from the distal tubule and collecting duct. Water follows the Na+ to increase BP and BV. Primarily under the control of RAS

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116
Q

RAAS system

A

The kidney’s response to decreased BP. Renin (juxtaglomerular cells) cleaves angiotensinogen –> active angiotensin I –> angiotensin II (ACE in lungs) –> release of aldosterone (adrenal cortex) –> increased Na+/H2O –> increased plasma volume –> increased CO –> increased BP

117
Q

Adrenal medulla

A

Responsible for the production of epinephrine and norepinephrine. These can be released in response to the SNS and some neurons

118
Q

Adrenal cortex

A

Secretes corticosteroids (steroid hormones). 3 S’s: Salt, Sugar, Sex

119
Q

Glucagon

A

released by α cells to increase glucose levels

120
Q

Insulin

A

released by β cells to decrease glucose levels. Stimulates fat and protein synthesis. Increases amount of GLUT 4 on the cell membrane

121
Q

Hyperglycemia

A

causes excess glucose in the urine which cause excess water excretion (increase urine volume)

122
Q

Type 1 diabetes

A

autoimmune destruction of β cells

123
Q

Type 2 diabetes

A

receptor level resistance to insulin

124
Q

Somatostatin

A

Inhibits glucagon, insulin, and GH release. Produced by delta cells and the hypothalamus

125
Q

Testes

A

secrete testosterone in response to LH and FSH

126
Q

Ovaries

A

secrete estrogen and progesterone in response to LH and FSH

127
Q

Estrogen

A

has positive and negative feedback effects. Estrogen levels initially negatively feedback on the hypothalamus and pituitary in order to allow the egg to grow (follicular phase), but it also positively feedback on those structures when the threshold is met and its time for ovulation

128
Q

Pineal gland

A

Secretes melatonin at night and serotonin during the day. Involved in the maintenance of circadian rhymes

129
Q

Erythropoietin

A

stimulate bone marrow to produce RBC’s in response to low blood O₂ levels

130
Q

Atrial natriuretic peptide (ANP)

A

Regulates salt and water balance. When the atria are stretched, ANP promotes Na excretion (increase urine vol) to decrease BP and BV

131
Q

Pathway of air

A

nares—> pharynx —> larynx (glottis)—> trachea —> bronchi —> bronchioles —> alveoli
(You Pop before you Lock )

132
Q

Residual volume

A

the small amount of air you have once all air has been breathed out of your lungs

133
Q

Vital capacity

A

max amount of air you can move. IRV + TV + ERV

134
Q

Tidal volume

A

Normal 500 mL of air you breath in and out. TV will increase in times of low pO2 (high altitude) —> increased air inhaled

135
Q

Dead space

A

No gas exchange occurs, but air still flows through these areas

136
Q

Chemoreceptors

A

primarily sensitive to to changes in CO₂ concentration and osmolarity

137
Q

Polycythemia

A

RBC multiplies due to conditioning at high altitudes. So the O2 carrying capacity is enhanced to take advantage of whatever O2 available

138
Q

Vasoconstriction

A

Causes conservation of thermal energy because blood is not able to pass as easily

139
Q

Vasodilation

A

causes dissipation of thermal energy when more blood passes through vessels

140
Q

Lysozyme

A

Innate immune enzyme that attacks the peptidoglycan walls of gram negative bacteria. Found in mucus of respiratory passages, tears, and saliva

141
Q

Oxygen dissociation curve

A

Measure of oxygen levels that are bound to a certain percentage of a Hb molecule.
Things that move the curve to the left = Hb increased affinity for O2
Things that move the curve to the right = Hb decreased affinity for O2 (oxygen unloading)

142
Q

Semilunar valves

A

separate the ventricles from the vasculature

143
Q

Tricuspid valve

A

separates the R atria and R ventricle

144
Q

Bicuspid (mitral) valve

A

separates the L atria and L ventricle

145
Q

Pulmonic valve

A

separates the R ventricle from the pulmonary artery

146
Q

Aortic valve

A

separates the L ventricle from the aorta

147
Q

Path of electrical conduction in heart

A

SA node —> atria —> AV node —> bundle of His —> purkinje fibers —> ventricles

148
Q

Hepatic portal system

A

blood leaving a capillary beds in the gut will pass through the hepatic portal vein before reaching capillaries in the liver

149
Q

Hypophyseal portal system

A

blood leaving capillary beds in the hypothalamus travels to capillaries in the anterior pituitary (for paracrine secretion)

150
Q

Renal portal system

A

blood leaving capillaries in the glomerulus travels through the efferent arteriole to the vasa recta

151
Q

Hematocrit

A

volume of RBC / volume of whole blood

152
Q

Granulocytes

A

Neutrophils, eosinophils, basophils. They contain cytoplasmic granules that are toxic to invaders. Released by exocytosis.

153
Q

Agranulocytes

A

Lymphocytes (primary responders) and monocytes

154
Q

Thrombopoietin

A

secreted by the liver and kidney and stimulates platelet development

155
Q

Blood pressure

A

ΔP = CO x TPR

156
Q

Baroreceptors

A

stimulate the SNS to increase vasoconstriction when BP is low and decrease it when BP is high

157
Q

Systolic blood pressure

A

occurs when the ventricles are contracting and blood is pumped into the lungs and aorta

158
Q

Diastolic blood pressure

A

occurs when the ventricles are refilling

159
Q

Cooperativity

A

Binding of 1 oxygen changes the conformation of hemoglobin (taught to relaxed) which increases the affinity for other oxygen molecules and increases the positive feedback of binding

160
Q

Bicarbonate buffer system equation

A

CO₂ + H₂O –> H₂CO₃ –> H⁺ + HCO₃⁻

*reversible

161
Q

Hydrostatic pressure

A

force that blood exerts against vessel walls

162
Q

Osmotic pressure

A

force generated by solutes to keep water in the blood stream. It is usually called oncotic pressure because it relates to plasma proteins

163
Q

Spleen

A

stores blood and activates B cells (mature and turn into plasma cells to produce antibodies) (adaptive immunity)

164
Q

Thymus

A

located in front of the pericardium. It produces T cells that kill infected cells directly (cytotoxic immunity)

165
Q

Adaptive immunity

A

defined by the presence of lymphocytes, either T or B cells, and includes both CD8+ cytotoxic T cells, CD4+ helper T cells, and B cells that present antigen and produce antibodies

166
Q

Innate immunity

A

Always active against infection but can not target specific invaders. Also called non-specific immunity

167
Q

Lymph nodes

A

Areas when immune cells group up to attack. B cells are activated here

168
Q

Gut associated lymphoid tissue (GALT)

A

immune tissue near the digestive tract. It includes tonsils and adenoids in the head, Peyer’s patches in the SI, and the appendix

169
Q

Lymphocytes

A

Agranulocytes responsible for antibody production, immune system modulation, and targeting of infected cells. Include NK cells, B lymphocytes, and T lymphocytes

170
Q

Monocytes

A

Phagocytic cells in the bloodstream. They become macrophages in the tissue. Ex/ microglia, langerhans cells, osteoclast

171
Q

Complement system

A

System that consists of proteins that act as nonspecific defense to bacteria in the blood. The classical pathway requires antibody binding and the alternative pathway does not

172
Q

Interferons

A

Proteins that are transcribed to prevent viral replication in other cells. They decrease the permeability of cells to make it harder for viruses

173
Q

Major histocompatibility complex (MHC)

A

protein that binds to the pathogen and carries it to the surface for adaptive immunity cells

174
Q

MHC class I

A

binds proteins already within the cells through an endogenous pathway

175
Q

MHC class 2

A

Binds invading antigens in an exogenous pathway. They display antigen presenting cells like macrophages and dendritic cells in the skin

176
Q

Macrophages

A

They endocytose invaders, digest them with enzymes, then present pieces of the invader to other cells by using MHC

177
Q

Natural killer cells

A

If a pathogen finds a way to down regulate MHC molecules, NK cells detect this and induce apoptosis in those infected cells

178
Q

Opsonized bacteria

A

bacteria marked with an antibody from a B cell that can be targeted by immune cells (phagocytize)

179
Q

Neutrophils

A

Phagocytic and target bacteria. They use chemotaxis to sense certain products given off by bacteria and follow them back to the source

180
Q

Eosinophils

A

Allergic reactions and invasive parasitic infection. They release histamine that causes inflammation by vasodilation and movement of fluid and immune cells from the blood to tissues

181
Q

Basophils

A

allergic responses

182
Q

Mast cells

A

release histamine and increase leakiness of capillaries in order for immune cells to leave the blood stream and into tissues

183
Q

Humoral immunity

A

involves the production of antibodies (immunoglobulins) produced by B cells (plasma cells)

184
Q

Clonal selection

A

When the adaptive immune system encounters an antigen, cells with receptors specific to the antigen are presented. The cells with the highest affinity for a given antigen proliferate

185
Q

Variable region (domain)

A

Tip of the Y. Also called the antibody binding region. Antibodies develop specificity so slowly because this region hypermutates to match the antigen

186
Q

Constant region (domain)

A

The long part of the Y. It contains receptors for NK cells, monocytes (macrophages) and eosinophils to initiate the complement cascade

187
Q

5 isotypes of antibodies

A

IgA, IgD, IgE, IgG, IgM

188
Q

Helper T cells (CD4⁺)

A

Coordinates the immune response and secretes lymphokines. They respond to MHC-II. Most effective against bacterial, fungal, and parasitic infection. Ex/ loss of these cells occurs in HIV infection

189
Q

Lymphokines

A

Secreted by lymphocytes to recruit other immune cells (plasma cells, cytotoxic T cells, macrophages) to an area and increase their activity

190
Q

Cytotoxic T cells (CD8⁺)

A

Directly kill virally infected cells by injecting toxins and causing apoptosis. They are better at fighting intracellular infection. Respond to MHC-I

191
Q

Suppressor (regulatory) T cells

A

They help tone down the immune response once infection has been contained (self-tolerance)

192
Q

Autoimmunity

A

when the immune system fails to distinguish between self and foreign

193
Q

Active immunity

A

the immune system is stimulated to produce antibodies against a specific pathogen after a weakened form of the antigen is presented (vaccines)

194
Q

Passive immunity

A

transfer of antibodies to an individual. Only the antibodies, not the plasma cells, are transferred. Ex/ mother to child through breast feeding

195
Q

Ghrelin

A

Released in the stomach when chyme is in the intestines. It stimulates hunger by stimulating the peptide NPY in the arcuate nucleus

196
Q

Leptin

A

Satiety hormone released from adipose tissue in response to glucose and insulin circulating. It suppresses NPY and appetite

197
Q

α-amylase

A

starts digestion of starches into carbohydrates by breaking their linkages

198
Q

HCl (digestion)

A

Secreted by parietal cells. Causes chemical breakdown of molecules and increase surface area of food so certain enzymes work

199
Q

Intrinsic factor

A

Secreted by parietal cells. Important for protection of vitamin B12 from pancreatic proteases

200
Q

Pepsinogen

A

Secreted by chief cells. Proteases that are cleaved to pepsin by the acidic environment

201
Q

Gastrin

A

Secreted from antrum G cells in the crypts into the blood. Stimulates motility in the intestines and stimulates parietal cells to secrete HCl

202
Q

Lipase

A

Secreted by chief cells. Continues hydrolysis of lipids

203
Q

Histamine (digestion)

A

It is the primary stimulus for HCl secretion

204
Q

Somatostatin (digestion)

A

Decreases HCl secretion, gastric emptying, GI motility, and GI hormone release. Works directly on parietal cells

205
Q

Brush border enzymes

A

Digest oligosaccharides and disaccharides into monosaccharides in the small intestine. Monosaccharides are the only form of carbohydrates that can be digested

206
Q

Enteropeptidase (enterokinase)

A

Activates trypsinogen in the SI and forms trypsin. Trypsin activates all the other pancreatic proteases to digest proteins into oligopeptides

207
Q

Dipeptidase

A

cleaves dipeptides to release free AA

208
Q

Aminopeptidase

A

removes the N-terminal AA from a peptide

209
Q

Secretin

A

Secreted by centroacinar cells in response to acid (chemoreceptors) —> increase pancreatic and intestinal buffers —> neutralizes acid. Causes the pH to lower to

210
Q

Chloecystokinin (CCK)

A

secreted by acinar cells in response to the entry of chyme in the duodenum. It stimulates bile production in the liver, gallbladder contractions, and relaxation of the sphincter of Oddi. It also stimulates digestive enzyme release from the pancreas

211
Q

Albumin

A

maintains oncotic pressure and is a carrier for clotting factors

212
Q

Net filtration pressure

A

HPg - (𝛑g + HPbs)

213
Q

Starling forces

A

Hydrostatic and oncotic pressure in the glomerulus and Bowman’s space

214
Q

Diuretics

A

inhibit reabsorption of Na in order to increase secretion

215
Q

Layers of epidermis

A

Stratum corneum, *stratum lucidum, stratum granulosum, stratum spinosum, stratum basale
(Come, Lets Get Sun Burned)

*Stratum lucidum is only present in thick hairless skin like the palms

216
Q

Langerhans cells

A

macrophages in the stratum spinosum. Present antigens to T cells

217
Q

Anion gap

A

We have our main cations in the plasma (Na and unmeasured) and our main anions as well (Cl, HCO3, and unmeasured). The anion gap is just the space (difference) between the Na and Cl in our plasma. When the anion gap is higher than normal, that means we have an acid gain. When the anion gap is normal, we have a base lose (losing HCO3

218
Q

Metabolic acidosis

A

A decrease in pH and a decrease in H2CO3 and compensates by decreasing pCO2

219
Q

Metabolic alkalosis

A

An increase in pH and an increase in H2CO3 and compensates by increasing pCO2

220
Q

Type 1 fibers

A

Slow twitch red fibers. They have high myoglobin content and derive energy aerobically. Ex/ muscles that support posture

221
Q

Type 2 fibers

A

Fast twitch white fibers. They contain less myoglobin and less iron. They contract rapidly but fatigue easily

222
Q

Myogenic activity

A

when smooth muscle can contract without NS input. Both smooth and skeletal muscle can exhibit this

223
Q

Myosin

A

Thick filament

224
Q

Actin

A

Thin filament and contains troponin and tropomyosin

225
Q

Sarcolema

A

Cell membrane of the myocyte. Able to propagate an AP

226
Q

T tubules

A

Distributes the AP of a myocyte to all sarcomeres

227
Q

Frequency summation

A

when prolonged exposure to a stimulus causes contractions to become stronger and longer

228
Q

Tetanus

A

muscle inability to relax after frequency summation. Prolonged tetanus results in muscle fatigue

229
Q

Vitamin D

A

activated by PTH and also promotes bone resorption

230
Q

Genes

A

DNA sequences that code for heritable traits

231
Q

Allele

A

Alternative form of a gene. Genetic combination is the genotype and the observable trait is the phenotype. It is classified by the degree of penetrance

232
Q

Locus

A

Particular location on a chromosome where alleles for a gene reside.

233
Q

Hemizygous genotype

A

only 1 allele is present for a given gene. Ex/ X chromosome in males

234
Q

Complete dominance

A

1 dominant and 1 recessive allele exists for a given gene

235
Q

Codominance

A

when more than 1 dominant allele exist for a given gene

236
Q

Incomplete dominance

A

when a heterozygote expresses a phenotype that is between (intermediate) the 2 homozygous genotypes. Ex/ RR (black hair) x rr (white hair)—> 4 Rr (grey hair)

237
Q

Autosomal dominant trait

A

autosomal means it is associated with one of the non-sex chromosomes. Dominant means you get one allele from the mother and one from the father

238
Q

Autosomal recessive trait

A

Presence of 2 defective genes. All children are effected because they receive a mutated allele from both parents

239
Q

Y-linked inheritance

A

when the only effected individuals are males

240
Q

X-linked dominant vs. X- linked recessive

A

1 copy of a defective gene is necessary for the diseased phenotype vs. 2 copies of a defective gene, one on each X chromosome, are necessary

241
Q

Penetrance

A

A population measure where there is a certain proportion of the population with a given genotype that actually expresses the phenotype

242
Q

Full penetrance

A

An individual has over 40 sequence repeats and would show symptoms of a disease

243
Q

High penetrance

A

Fewer sequence repeats and may or may not show symptoms

244
Q

Reduced pepentrance

A

Almost no sequence repeats and no symptoms

245
Q

Expressivity

A

The variability in phenotypes for the same genotype in an individual

246
Q

Transposons

A

insert themselves into the genome and can disrupt the gene if they are within the coding sequence

247
Q

Genetic leakage

A

Flow of genes between species. Individuals from different but closely related species can mate and produce hybrid offspring

248
Q

Genetic linkage

A

The tendency of genes located close together on a chromosome to be inherited together during meiosis

249
Q

Genetic drift

A

the change in composition of a gene pool by chance (Ex/ random mutations)

250
Q

Founder effect

A

Extreme type of genetic drift where a small population leads to isolation from other populations due to natural barriers, or bottlenecks. This leads to inbreeding

251
Q

Test cross

A

Used to determine an unknown genotype. The unknown genotype (Px where x = P or p) is crossed with an organism known to be homozygous recessive (pp)

252
Q

Recombination frequency

A

The likelihood of 2 alleles seperating from each other during crossing over is proportional to the distance the genes are from each other on the chromosome. Genes farther apart are more likely to cross over

253
Q

Hardy Weinburg equillibrium

A

Tells us when gene frequencies of a population are not changing and are stable
p² +2pq +q² = 1
p + q = 1
- Where p is the frequency of the dominant allele and q is for the recessive
p² = frequency of homozygous dominant allele
2pq = frequency of heterozygotes
q² = frequency of homozygous recessive allele

254
Q

Inclusive fitness

A

a measure of an organisms success in a population

255
Q

Polymorphisms

A

naturally occurring differences between members of the same population

256
Q

Speciation

A

formation of a new species though evolution

257
Q

Divergent evolution

A

From a common ancestor, 2 species develop different characteristics. Ex/ humans and monkeys

258
Q

Parallel evolution

A

2 species independently evolve in similar ways

259
Q

Convergent evolution

A

development of similar characteristics with no common ancestor. Ex/ fish and dolphins

260
Q

Corticosteroids

A

Glucocorticoids, mineralocorticoids, and cortical sex hormones

261
Q

Refractory period

A

period of time following an AP where a neuron is not able to depolarize

262
Q

Relative vs. absolute refractory period

A

Greater than normal stimulation can cause an AP vs. no amount of stimulation is able to cause an AP

263
Q

Corticotropin releasing factor (CRF)

A

tropic hormone released from the hypothalamus that causes ACTH releases from the anterior pituitary

264
Q

Gonadotropin releasing hormone (GnRH)

A

tropic hormone released from the hypothalamus that causes LH and FSH release from the ant. pit.

265
Q

Thyroid releasing hormone (TRH)

A

tropic hormone released from the hypothalamus that causes TSH release from the ant. pit

266
Q

Orthologous genes

A

homologous genes where a gene diverges after a speciation event, but the gene and its main function are conserved

267
Q

Hershey-Chase experiment

A

Used to determine that DNA is heritable genetic material. They injected bacteriophages with radiolabeled DNA (phosphorus) and protein (sulfur) and allowed them to infect non-labeled bacteria. Only the DNA was found in the cells

268
Q

Functions of lymphatics

A

Removal and destruction of pathogens, drain excess fluid from interstitial spaces (not the CNS), absorb fats from the GI tract.

269
Q

Cytokines

A

Chemical substances released by macrophages that stimulate inflammation and recruit additional immune cells to the area

270
Q

Isotype switching

A

Cells can change which isotype of antibody they produce when stimulated by specific cytokines

271
Q

Constant expressivity

A

If expressivity is constant, all have the same phenotype

272
Q

Variable expressivity

A

If expressivity is variable, there are people with the same genotype but varying phenotypes

273
Q

Disruptive selection

A

Occurs when two extreme phenotypes are selected over the norm (no incomplete dominance) leading to the creation of subpopulations that grow more disparate over time (speciation)

274
Q

Collagen

A

Principal extracellular component of connective tissue

275
Q

In vivo

A

refers to when research or work is done with or within an entire, living organism

276
Q

In vitro

A

used to describe work that’s performed outside of a living organism

277
Q

Testosterone

A

Secreted by leydig cells in the testes. Associated with risky and aggressive behavior (secretion increases during puberty)

278
Q

Diabetic ketoacidosis

A

Insufficient insulin in the body causes the body to break down fatty acids into acidic ketone bodies. Causes increased excretion of glucose (decreased absorption), H+, and water

279
Q

Smooth endoplasmic reticulum

A

Lipid synthesis (steroids, oils, wax) and detoxification of certain drugs

280
Q

Directional selection

A

The shift in allele frequencies of a population to variants of one extreme

281
Q

Orexigenic vs. anorexigenic peptides

A

Peptides that increases appetite vs. peptides that suppress appetite

282
Q

Effects of acute vs. long-term stress

A

PNS is suppressed to divert resources to immediate problems vs. energy is used to cope with stress must be replaced like increasing appetite and sleep

283
Q

Chemiosmosis

A

The movement of ions across a semipermeable membrane, down their electrochemical gradient

284
Q

ABC transporters

A

ATP binding cassete transporters are transmembrane proteins that are membrane associated ATPases

285
Q

Vibrissae

A

Nasal hairs

286
Q

Node of Ranvier

A

Unmyelinated regions of a neuron that allow for saltatory conduction of action potentials. These are the only places where ion exchange occurs

287
Q

Diploid vs. haploid

A

Containing 2 copies of each chromosome (2n) VS. containing 1 copy of each chromosome (n)

288
Q

Negative feedback loop

A

Used to maintain homeostasis. A change in a physiological variable triggers a physiological response that counteracts the initial variable

MCAT (7 decks)

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