bio 2

Nucleus

Has chromosomes with DNA that provides the instructions to make proteins

Management – sends out instructions (DNA –> RNA)

benign

not responsible for identified effects

Genetics

this testing refers to speciic testing of areas of known function

Genomic

this testing refers to evaluation of large segments across the entirety of genetic material which may or may not have known function

pathogenic

responsible for identified effects

variant of uncertain significance

unclear if responsible for identified effects

catabolic pathways

degradation of complex molecules into simpler ones

catabolic pathways

Glycolysis

pyruvate dehydrogenase complex

kreb’s cycle/ citric acid cycle

electron transport chain

Glycolysis

converts glucose into pyruvate through a sequence of ten enzyme-catalyzed reactions

pyruvate dehydrogenase complex

linking the glycolytic pathway to the oxidative pathway of the tricarboxylic acid cycle

electron transport chain

a series of four protein complexes that couple redox reactions, creating an electrochemical gradient that leads to the creation of ATP in a complete system named oxidative phosphorylation

kreb’s cycle/ citric acid cycle

completes the oxidation of glucose by taking the pyruvates from glycolysis

central dogma of molecular biology

the flow of genetic information in cells from DNA to messenger RNA (mRNA) to protein

produces enzymes for catalysts

capillaries

transports the glucose to the blood

lacteal

acts as the support so that the microvilli can stand

cortisol

a hormone that eneables the muscles contracts which gives a lot of pain

pyrimidines

thymine and cytosine

purines

adenine and guanine

Ribosomes

The protein factories of the cell

Workbench – makes products (proteins)

Cytoplasm

Includes everything found inside of the cell membrane except for the nucleus

Cell membrane

Separates the inside of the cell from the outside environment;

Regulates what gets into and out of the cell

Cytoskeleton

Gives the cell its shape and provides pathways for transport

Lysosome

Contains chemicals that break down food particles and worn out parts

Cleanup crew – disposes of old and worn out products and equipment; prepares them for recycling

Mitochondria

Produce most of the cell’s ATP

Powerhouse – provides energy in a form the factory/cell can use (ATP)

Golgi apparatus

Receives proteins form the ER, packages them, and sends them to other parts of the cell

Transport – moves products (proteins) around in factory/cell

Endoplasmic reticulum (ER)

Smooth ER: makes lipids

Rough ER: processes proteins for secretion

Rough ER

Processing – prepares products (proteins) to leave factory/cell

Homeostasis

from the two Greek words ”homo” - same and “statis” – stable.

Homeostasis

a self-regulating process by which an organism can maintain internal stability while adjusting to changing external conditions.

Homeostasis

o Thermoregulation (temperature)

o Osmoregulation (water)

o Gas Exchange

o Blood Glucose

o Guard Cells

Homeostasis

It also responsible for the regulation and internal maintenance of the body. The body works best when internal conditions are within an acceptable range.

Homeostasis

it typically involves negative feedback loops that counteract changes of various properties from their target values, known as set points.

positive feedback loops

amplify their initiating stimuli, in other words, they move the system away from its starting state

Child birth

having a child while in labor makes a female body contracts in such a way that their adrenal glands (an organ that is on top of the kidneys) secretes a lot of cortisol a hormone that enables the muscles contracts which gives a lot of pain.

Feedback loops

a biological occurrence where the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).

Thermoregulation

Hypothalamus scans temperature of blood as it passes through

Too high 🡪 blood vessels:

dilate, sweating occurs

Too low 🡪 blood vessels:

constrict, shivering

osmoregulation

Regulation of the balance of water and solutes (salt, ions) in the body

Aquatic Organisms

(freshwater) protists

freshwater fish

Freshwater fish

environment is hypotonic to the fish; fish take in lots of water

Freshwater fish

Solution 🡪 fish excrete LOTS of very dilute urine to conserve solutes.

Saltwater fish

environment is hypertonic to the fish; fish loses water to osmosis.

Saltwater fish

Solution 🡪 fish have specialized gills to excrete excess ions

Osmoregulation in humans

a. Terrestrial Animals

i. Water is constantly being lost through evaporation, perspiration, urination

1. Water lost through these avenues needs to be replaced by drinking and eating

ii. Concentration of urine allows solutes to be excreted while conserving water (kidneys)

Terrestrial Animals

Water is constantly being lost through evaporation, perspiration, urination

Terrestrial Animals

Water lost through these avenues needs to be replaced by drinking and eating

Terrestrial Animals

Concentration of urine allows solutes to be excreted while conserving water (kidneys)

Guard Cells (Plants)

a. Leaves take in CO2, release O2 and H2O through stomata

b. Guard cells surround the stomata

i. Water abundant 🡪 water pressure HIGH, stomata OPEN, release water, CO2 enters

ii. Water scarce 🡪 water pressure LOW, stomata CLOSED, loss of water limited

c. Generally 🡪

i. Stomata open during the day (photosynthesis)

ii. Stomata closed during the night (decreased photosynthesis, prevent water loss)

iii. Exceptions 🡪 HOT DRY conditions may result in closed stomata during the day

stomata

Leaves take in CO2, release O2 and H2O through??

Water abundant 🡪 water pressure HIGH

stomata OPEN, release water, CO2 enters

Water scarce 🡪 water pressure LOW

stomata CLOSED, loss of water limit

photosynthesis

Stomata open during the day

(decreased photosynthesis, prevent water loss)

Stomata closed during the night

Exceptions 🡪 HOT DRY conditions

may result in closed stomata during the day

Respiration (Gas exchange)

lungs

Respiration (Gas exchange)

a. Oxygen-rich air (poor in CO2) is taken in during inhalation; moves to alveoli

b. Oxygen-poor blood (rich in CO2) vessels surround the alveoli

c. Passive transport moves the oxygen from alveoli into the blood, CO2 from blood into the alveoli

d. Oxygen delivered to cells through the blood vessels; CO2 expelled during exhalation

Oxygen-rich air (poor in CO2)

is taken in during inhalation; moves to alveoli

Oxygen-poor blood (rich in CO2)

vessels surround the alveoli

Passive transport

moves the oxygen from alveoli into the blood, CO2 from blood into the alveoli

Oxygen

— delivered to cells through the blood vessels;

CO2

expelled during exhalation

Blood circulation (Blood glucose)

a. Blood sugar too high:

i. Pancreas releases insulin; body cells take in glucose and moves it to long term storage in liver (glycogen)

b. Blood sugar too low:

i. Pancreas releases glucagon; stimulates liver to break down stored glycogen (into glucose) and release into bloodstream.

Blood sugar too high

Pancreas releases insulin; body cells take in glucose and moves it to long term storage in liver (glycogen)

insulin

Pancreas releases —-; body cells take in glucose and moves it to long term storage in liver (glycogen)

glycogen

take in glucose and moves it to long term storage in liver (—-)

Blood sugar too low

i. Pancreas releases glucagon; stimulates liver to break down stored glycogen (into glucose) and release into bloodstream.

glucagon

Pancreas releases —-; stimulates liver to break down stored glycogen (into glucose) and release into bloodstream.

glucose

stimulates liver to break down stored glycogen (into —)

Genetics

Study of heredity and variation of essential character

Genetics

first coined in 1905 to describe the study of heredity

Heredity

tendency of offspring to resemble their parents

Variation

tendency of offspring to vary from their parents

“to give birth”

Greek “genno”, γεννώ; ???

Gregor Johann Mendel

Father of Classical Genetics

Gregor Johann Mendel

During his time he experimented of pea plants and made observations by counting all the offsprings of the cross fertilized pea plants which he discovered 7 characteristics that he identified to certain variations and how they are being past form parents to offspings.

Gregor Johann Mendel

He paved way to classical genetics during 1865 on particulate inheritance.

Reginald C. Punnett

Later on geneticist—- devised the Punnett square in 1905.

Punnett square

The diagram is used by biologists to determine the probability of an offspring having a particular genotype.

GENOTYPE

genetic make-up/composition

PHENOTYPE

aspects of a person you can see

MUTATION

alteration in the genetic code from what is expected

variant

Does not necessarily communicate a change is pathogenic

Chromosomes

are the structures that store genetic information in the form of DNA

46

Humans have —- chromosomes

autosomes

22 pairs

sex chromosomes

1 pair

nucleotides

The basic building block of nucleic acids (RNA and DNA).

nucleotides

consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA) attached to a phosphate group and a nitrogen-containing base.

adenine (A), cytosine (C), guanine (G) and thymine (T)

The bases used in DNA are ??

nitrogenous bases

Genetic disorders/diseases

caused by mutations

mutation

— is any type of change in genetic material

mutation

are caused by:

i. Radiation

ii. Chemicals

Radiation

X-rays, sun exposure

chemicals

May contain toxic substances

sex cells

You can pass on mutations to your offspring only if the mutation is in your —

Whole chromosomes are missing OR there are extra chromosomes

This is caused by disjunction which happens during meiosis when chromosomes did not segregate or separate and distribute to the gametes properly

Trisomy 21

Down’s Syndrome

Trisomy 21

Extra copy of chromosome 21

The incidence of Down syndrome is estimated at 1 per 800 to 1,000 births, although these statistics are heavily influenced by the age of the mother.

Trisomy 13

Patau syndrome