Biology part 2

Aneuploidy

a genome with extra or missing chromosomes, often caused by nondisjunction

Oncogene

mutated proto-oncogenes increasing cancer risk. Proto-oncogenes are genes involved in regulating cell growth and division

A man and a woman have normal skin color but both have one parent with albinism, which is caused by an autosomal recessive allele. If the couple intends on having 2 children, which of the following is the probability that both children will have albinism?

1/16. Probability that their child will have albinism is ¼ (aa) and multiply this by ¼ again because each child is independent event ( 2 children) so ¼ x ¼

Mitosis vs Meiosis in terms of homologous chromosomes

Mitosis, homologous chromosomes are there but instead of pairing up they individually line up stacked on top of each other so each chromosome’s sister chromatid can separate.

Meiosis, homologous chromosomes are there but they pair up with each other so they split from their partners in Anaphase 1, and then each chromosome’s sister chromatids are separated in Anaphase 2 resulting in 4 cells

Nondisjunction in Meiosis 1 and 2

Parathyroid gland general function

increases blood calcium Ca2+ levels

fitness

measured by the # of fertile offspring an organism can produce that can reach reproductive age

in mammals or humans what does yolk sack serve purpose

first site of red blood cell synthesis

Memorize

"Tell Di, Mes Met My"🗣️💬

Where are embryonic stem cells from

inner cell mass of the blastocyst. pluripotent cells

What is Catastrophism and who made this theory

Earth‘s geography and life were shaped by catastrophic events such as natural disasters made by Georges Cuvier

Modern cell theory

1. All living organisms are composed of one or more cells.

2. The cell is the basic unit of structure, function, and organization in all organisms.

3. All cells come from preexisting, living cells.

4. Cells carry hereditary information.

What is a Labile cell and what kind of cell type/origin of the body can be classified as it?

continuously multiply and divide throughout life.

epithelium of the skin

What does the parathyroid gland do generally?

increases calcium levels in the blood by stimulating osteoclast activity and calcium release

What does calcitonin do and where does it come from

Hormone that decreases blood calcium levels by stimulating osteoblast activity. made by thyroid gland

Where does filtration occur in kidney

renal corpuscle of the nephron

what is it? the primary blood filteration structure which has glomerulus which is housed inside Bowman’s capsule, and renal tubules

What is the filtrate and where does it go

it is the fluid that goes through glomerulus to the rest of the nephron. It is pushed into Bowman’s capsule to enter nephron.

What kind of particles cannot filter through glomerulus

too large ones like blood cells and immunoglobins and immune cells cannot.

What regulates and facilitates the movement of filterate through glomerulus

hydrostatic pressure

State the steps and location of filtration

filtrate goes to proximal convoluted tubules → loop of henle (descending then ascending arms) → distal convoluted tubules → collecting ducts

What is reabsorption (kidney wise)? Where does it happen

Reabsorption is the process in which a substance is pulled out of the nephron and brought back into the blood. Most reabsorption happens in proximal convoluted tubule

What are some molecules that can be reabsorbed in the kidney? Proximal convoluted tube and distal convoluted tube

proximal:

glucose,

Na+/Cl-,

amino acids

distal convoluted tube:

glucose,

ions,

water

Glucose is the only one that stays in the body (doesn’t remain in nephron for excretion)

What is secretion and where does it happen?

in which a substance is removed from the blood and sent back into the nephron. Happens in the proximal convoluted tubule

What kind of molecules are secreted through kidney

acids, bases, ammonia, drugs, and ions

What is neurulation

embryonic developmental process where the notochord stimulates the development of neural tube from ectoderm cells

What is a notochord and where is it developed from

Notochord: formed by cells of dorsal surface of mesoderm.

→ stimulates cells of the ectoderm to thicken, resulting in the formation of the neural plate

How does the neural tube form?

In the ectoderm layer, the neural plate develops and folds into a neural fold which then keeps folding until it becomes neural tube.

During embryonic development, what develops directly above the notochord?

neural tube

Archenteron

center cavity of the gastrula eventually develop into the gut tube.

invagination of the primitive streak during gastrulation

Halophiles

extremophiles that live in environments with high salt concentration.

Which of the following structures is the pacemaker of the heart?

Sinoatrial node

Interspecific competition

interactions between members of different species

Niche

all the biotic and abiotic resources in the environment used by an organism.

The pancreas releases enzymes used in digestion. Which of the following pancreatic enzymes is used to cleave peptide chains?

Chymotrypsin

What digestive enzymes are released from the pancreas

Chymotrypsin and trypsin

Which organ secretes pepsin

stomach

Platyhelminthes

heterotrophic, aquatic worms like flatowrms, trematodes, flukes, tapeworms, etc🪱🪱

can perform sexual or asexual reproduction

Histone and their function

protein complex that wraps tightly around DNA. How tight the histone is determines how much DNA is available for RNA polymerase to attach to

Euchromatin

less condensed regions of the chromatin with active genes readily accessible

Heterochromatin

highly condensed regions

Sarcoplasmic reticulum

unique smooth ER found around muscle fiber.

After action potential reached this organelle, it releases Calcium ions Ca2+ into the muscle or the actin and myosin which initiates contraction

How does the steps go for muscle contraction? breif overview

Starts with action potential arrives at neuromuscular junction,

and then Acetylcholine is released,

ACh binds to receptors, opening Na+ ion channels

which then lead to more action potential down sarcolemma.

This action potential travels along T tubules resulting in sarcoplasmic reticulum to release Ca+ ions.

Ca2+ binds to troponin,

causing it to remove tropomyosin from binding site on actin,

allowing myosin heads to bind to actin

Cilia vs Microvilli and their locations

Cilia is found in respiratory tract while Microvilli are found on enterocytes or small and large intestine. Cilia sweep debris while microvilli absorb

What happens during depolarization?

voltage gated Na+ channels open leading to influx (going IN) of Na+ ions FIRST.

What happens during repolarization?

Na+ channels inactivate and K+ channels open to allow them to escape neuron. Na+ channels ARE CLOSED

Limbic system function

memory, emotion, thirst, hunger, temperature, libido

Cerebral cortex

speech and motor regulation

Rank the organs from highest blood pressure to lowest blood pressure

Aorta (largest) →

arteries →

arterioles →
capillaries →

venules →

veins →

superior and inferior vena cava →

Aldosterone primarily acts on the _____ and functions to ______

collecting duct and distal convoluted tubule; increase water reabsorption.

what is aldosterone

steroid hormone made by adrenal cortex.

Increase blood pressure by affecting kidney

Increases Na+ reabsorption, which increases water accumulation leading to increase pressure

Cyclic amp cAMP

2ndary messenger for hydrophilic hormones that bind on the cell membrane receptor. Activates protein kinase A and phosphorylation cascade that causes gene expression, cell growth, etc

Inositol triphosphate IP3

2ndary messenger. binds to ER to trigger release of Ca2+ regulating muscle contraction, Neurotransmitters, and cell death

DAG diacylglycerol

2ndary messenger. triggers signaling cascades activating Protein Kinase C regulating proliferation, survival etc

Ca2+ ions

2ndary messengers. trigger rapid and localized increases in cytoplasmic conc. regulating apoptosis, contraction, etc

codon

sequence of 3 nucleotides for amino acid

Which molecule has a very strong binding affinity for hemoglobin and is difficult to remove?

oxygen

Gonadotropin-releasing hormone (GnRH)

released by hypothalamus.

A type of tropic hormone where it does not directly induce their effect on target tissue.

This hormone triggers release of LH and FSH

For a pedigree what does the two horizontal lines represent and what kind of allele does it usually mean

inbreeding. recessive allele

What does the Q10 value mean

measure the temperature sensitivity. tells rate of biological processes changes when an organism’s internal temperature shifts by 10°C

Example: “the Q10 value of an organism is 2”.

Hence, if the internal temperature of this organism increases by 10°C, its metabolic rate will double 2x

if the internal temperature of this organism decreases by 10°C, its metabolic rate will decrease by half 1/2

What happens during the light dependent reactions

light is used to make ATP and NADPH

What happens during the light independent reactions

calvin cycle. fix 6CO2 into 1 organic glucose

Do prokarytoes have promoter sequences

yes

RH blood protein negative meaning

if you are RH - that means you lack the RH protein on your RBC which is abnormal

What hormones dot he thyroid gland produce

Thyroxine (T4), Triiodothyronine (T3), and Calcitonin

In human gamete production during meiosis, how many chromatids are present during Anaphase I?

92

What are the prokaryotic ribosome subunits

50S and 30S combining to make 70S

Altruism

decrease the individual’s fitness but increase their group’s overall fitness whether making a personal sacrifice

Ecological succession

process by which an ecological community changes over time (a change in the species inhabiting an area).

This change may occur unto two general types: primary and secondary succession.

Ileocecal valve

separates the small and large intestines and regulate the passage of digested material between them

Sphincter of Oddi

regulates flow liver bile and pancreatic enzymes

Pyloric sphincter

allows partially digested food (chyme) to pass from stomach to duodenum (first part of small intestine)

Esophageal sphinter

allows food to pass from the esophagus into the stomach

Protostomes

one of the 2 major lineages of bilaterally symmetrical animals.

Annelids, mollusks, arthropods

mouth develops 1st

spiral cleavage

determinate cleavage

schizocoel

deuterostomes

echinodermata, chordates

anus develops first

radial cleavage

indeterminate cleavage

enterocoel

Radial cleavage

stacked, identically sized cells aligned parallel/perpendicular to the axis

Spiral cleavage

unequal sized, spiral cells

which of the following layers of the skin is responsible for the production of new skin cells

stratum germinativum or in other words the stratum basale

Integumentary system

made up of skin and appendages

Fur vs hair

fur is thicker than hair

Feather vs hair

feather is harder

Systemic circuit

distributes oxygenated blood containing nutrients to all body tissues, carrying blood away from the heart via the arteries. Arteries leave from the left ventricle

Pulmonary circuit

pumps deoxygenated blood through the pulmonary arteries to capillaries in the lungs for gas exchange. Pulmonary arteries come from the right ventricle

Analogous structures

structures that emerge when two different species without a common ancestor face similar environmental pressures

Homologous structure

structures shared between two species that do share a recent common ancestor but diverged

Tetrad

when the sister chromatids of the homologous chromosome pairs tightly align happens during prophase 1

Of the following structures in the integumentary system, which is found only in class Mammalia?

Dermis

A male bodybuilder injects himself with significant amounts of testosterone and other androgens on a regular basis. Which of the following would be seen as a result?

decreased spermatogenesis

Testicle cell function

sperm production or spermatogenesis

Which gland/organ does the testosterone hormone target

testicle cells

hCG hormone

prevents❌ the disintegration of the corpus luteum. Also used as a biomarker to detect if someone is pregnant

Induction

the process of cells influencing the development of other adjacent cells by signaling a change in their gene expression

Which phyla display radial symmetry

Cnidaria and Echinodermata 

Which phyla does not exhibit radial or bilateral symmetry?

Porifera

In humans when a female is born, the development of her oocyte is arrested in which of the following stages?

metaphase 1 of meiosis

Surfactant

coats inner surface of alveoli🫁, works to reduce surface tension in alveoli

Incomplete dominance

intermediate inheritance where there is a blend of the alleles

Co dominance

both alleles in genotype are seen in the phenotype

Rod in the eye function

contain pigments called rhodopsin involved in night vision and seeing in the dark

Cone cells in the eye

responsible for seeing color

R selected species

produce many offspring and dedicate minimal parental investment (e.g. frogs, fish, and rabbits)

most offspring die early

Type 3 curve