Bio 162 Lab Final
what is Brassica oleracea
(wild cabbage) Brassica oleracea is a plant species that includes many common foods as cultivars, including cabbage, broccoli, cauliflower, kale, Brussels sprouts, collard greens
Endocrine system
- Collection of organs that secrete chemical signals into the bloodstream in response to a stimulus - Postal service: delivery of message is slow - Effects last longer
Auxin in Gravitropism
- In roots, auxin inhibits cellular elongation in areas where it's more concentrated (unlike shoots) - In response to the pull of gravity, auxin is redistributed to be more concentrated on the underside of the root - This causes decreased cell elongation on the underside compared to upperside, so the root bends downwards
Auxin in Phototropism
- In shoots, auxin promotes cell elongation in areas where it's more concentrated - Auxin is transported from the apical meristem to the side of the stem opposite the source of light - A greater concentration of auxin on the "shady side" triggers greater cell elongation on that side, causing the plant to bends towards the light
What is a fruit?
- Mature ovary containing seeds - evolved to protect or disperse seeds - thickened ovary walls: pericarp (includes the endocarp, mesocarp, exocarp) - then inside the pericarp is the seeds (seed coat, endosperm)
auxin
- Plant hormone that regulates growth & influences cellular elongation in roots & shoots in response to light and gravity - Produced in the apical meristem of plants - Auxin promotes cellular elongation in shoots, but inhibits elongation in roots - Auxin suppresses lateral growth overall - Auxin also inhibits dormant lateral buds from growing
Nervous System
- Telephone system: fast direct messsages - Effects are quick
when leaf abscission happens...
- photosynthesis and respiration decreases - temperatures decrease - photoperiod shortens - auxin production slows
Simple Fruit
A fruit derived from a single carpel or several fused carpels. - dry or fleshy - berry (tomato), drupe (peach), Hesperidium(orange), Pome(apple - legume (pea), nut (acorn), Grain (corn), sunflower
Apical Dominance
A growth habit in which most of a stem's growth occurs at the apical meristem of the shoot - Occurs because of continuous flow of auxin from the tips of growing shoots to the tissues below, signaling the direction of growth - If the signal stops it means that growth has been interrupted and lateral branches sprout and begin to take over for the main shoot
What is the main anatomical difference between the anterior and posterior pituitary glands? What is the main functional difference?
Anatomical: the anterior is not connected to the hypothalamus, the posterior is Functional: The anterior is endocrine tissue that secretes hormones and the posterior is nervous tissue that conducts action potentials
immune system parts
Bone marrow: produce blood cells and store fat Thymus: produces progenitor cells (t-cells) that kill cancer Lymph nodes: filter foreign particles Spleen: filters and recycles blood cells Tonsils: traps the germs that are breathed in Leukocytes (white blood cells): protect the body from foreign particles
What flower has a modified stamen?
Callistemon- Bottle brush
fly pollinated flowers
Carrion flowers smell like rotting flesh
Which part of celery, onion and carrot is modified? Modified for what purpose?
Carrot: modified tap root to store nutrients Onion: modified leaves to Celery: modified leaf, we eat the petiole, used for
Hormone
Chemical signal circulated through body fluids that affects distant target cells
Chronic stress can result in very high levels of cortisol. The hypothalamus and anterior pituitary stop responding to these levels of cortisol through negative feedback, and as a result cortisol levels can stay high. Explain the effect this might have on the strength of the immune response in chronically stressed animals.
Chronically high levels of cortisol would suppress thymus activity, blocking immune function. This is why people are more likely to get sick if they are stressed!
testosterone feedback
Hypothalamus -> GnRH -> anterior pituitary -> LH -> Testes make testosterone. Testosterone acts in a negative feedback by turning off the glands individually when enough is made
Reticular fibers in lymph node
Form & function: Lymph node has thread-like reticular fibers that filter pathogens + debris from lymph system
Neutrophil
Function: Defend the body against bacterial and fungal infection via phagocytosis (they eat the "bad guys") Most abundant type of white blood cell granulocyte Multi-lobed nucleus (typically tri-lobed)
Monocyte
Function: Defends body against pathogens via phagocytosis, delivers pieces of pathogens to lymphocyte T cells (for adaptive immune system, antibody production) < nucleus to cytoplasm ratio Normally have kidney-shaped nucleus
Eosinophil
Function: Primarily respond to parasitic infections, more numerous in mucous membranes. Secrete chemicals that destroy parasites that are too large to phagocytize (e.g. parasitic worm). One of the least common/abundant types of leukocytes granulocyte Pink-ish granules in cytoplasm Bi-lobed nucleus
Basophil
Function: Responsible for inflammatory reactions during immune response by producing histamine (a vasodilator) and heparin (a blood thinner). Responsible for chronic allergic diseases (asthma, anaphylaxis, hay fever). One of the least common/abundant types of leukocytes Blue-ish granules in cytoplasm Large nucleus relative to cytoplasm ratio granulocyte
Lymphocyte
Function: adaptive immune system (allows the body to remember infections and fight them better upon re-infection) 3 major lymphocyte types: B Cells, T Cells, Natural Killer Cells Smaller than monocyte > nucleus to cytoplasm ratio
Cortisol Hormone Feedback
Hypothalamus -> CRH -> Anterior pituitary gland -> ACTH -> Adrenal Gland -> Cortisol Cortisol acts as a regulator that shuts off the production of more cortisol by going to the individual glands and binding to them
Menstrual Cycle
Hypothalamus -> GnRH -> anterior Pituitary gland -> LH/FSH -> Ovaries -> Estrogen and Progesterone -> uterus Estrogen can act as a positive feedback loop on day 12-14. Estrogen and Progesterone act as a negative feedback for the rest of the cycle
Which signal is stronger in plants, gravitropism or phototropism?
Gravitropism is usually stronger than phototropism
negative phototropism
growth of a plant away from light
Thyroid Hormone Feedback
Hypothalamus -> TRH -> Anterior pituitary Gland -> TSH -> Thyroid Gland makes thyroid hormone. thyroid hormone acts as a threshold to turn off the thyroid producing glands when there is an abundance of thyroid hormone.
anterior and posterior pituitary gland
Intermediary between hypothalamus and endocrine glands. Anterior Pituitary Gland - endocrine tissue Posterior Pituitary Gland - nervous tissue
interstitial cells in testes
Interstitial cells produce testosterone, which is required in large, localized concentrations for normal sperm development.
what is a p value (with two means)
Probability of an observed result as or more extreme assuming the null hypothesis is true the probability of getting two means that are at least "this" different This refers to a t statistic value derived from a sample mean
positive phototropism
growth of a plant toward light
Gravitrpism
Movement/growth in response to gravity
Phototropism
Movement/growth in response to light
positive gravitropism
growth of the roots towards the force of gravity
testes
look at slide on power point from lab 8
Several types of leukocytes are collectively called "phagocytes". Which types are these?
neutrophils and monocytes
The ability to taste the chemical PTC is determined by a single gene. Tasters have at least one copy of the dominant allele and non-tasters are homozygous recessive. In the natural world, would there be an advantage or disadvantage to being a "taster"?
There is an advantage to being a taster because they are able to detect the PTC toxin and choose not to eat it while non-tasters will eat it.
What is the functional connection between the interstitial cells and the developing sperm cells in the testis?
They produce testosterone in the presence of luteinizing hormone for the developing sperm to use
elongation in roots
auxin inhibits growth
Erythrocyte
a mature red blood cell Function: important for oxygen transport
Why might certain parts of your body have lower two-point thresholds than other parts?
because it is necessary for survival that we are able to feel light sensations like hot and cold in certain areas, while its not so crucial for other body parts to be so sensitive
Describe one situation where a flower and its pollinator show coevolution.
bees appear to be especially adept at perceiving bilateral symmetry and the colors blue and yellow, and at manipulating flower parts. So plants being pollinated by bees are subject to a strong selective pressure favoring bilateral symmetry and those colors
Platelets
blood clotting
Hypothalamus
brain region controlling the pituitary gland
bee pollinated flowers
bright purple
Ethylene
hormone that triggers maturation ethylene is strongly associated with three aspects of senescence in plants: fruit ripening, flower fading, and abscission.
study Wanyes world fruits
https://www2.palomar.edu/users/warmstrong/fruitid1.htm
lower P values means (for 2 p values)
indicates strong evidence against the null hypothesis, so you reject the null hypothesis. there is more evidence of differences between the population means lower probability of these means being from the same population
High P values means (for two p values)
indicates weak evidence against the null hypothesis, so you fail to reject the null hypothesis there is less evidence of differences between population means higher probability that the means could be from the same population
what flower has specialized sepals?
orchid
hummingbird pollinated flowers
red and have long tubes with nectar at the bottom
How do the different phototropic and gravitropic responses make sense from a functional standpoint of the plant organs
roots always follow gravity down so they can reach water while shoots grow up because it allows them to obtain sunlight. Leaves also grow towards the light so they can obtain he most sunlight
Suppose testosterone regulation suddenly switched from negative to positive feedback. what would happen?
testosterone levels would skyrocket because the more testosterone that is produced, the more it is stimulating the glands to produce more
Some bodybuilders abuse anabolic steroids like testosterone. What effects would this have on the size of the testes? Explain.
the testes would shrink due to the overflow of testosterone in the body. Since it is a negative feedback loop, the testosterone produced by the testes and injected will tell the glands to stop making testosterone in the testes.
simple, aggregate, multiple
three types of fruits simple: develops from a single ovary containing one or more carpels (apricot) aggregate: a fruit formed from several carpels derived from the same flower, e.g. a raspberry. multiple: a fruit formed from carpels derived from several flowers, such as a pineapple.
The table below shows the minimum concentrations of substances needed to stimulate the sweet, sour, salty, and bitter taste receptors in humans. Which of the substances are humans most sensitive to? Explain the patterns you see in terms of human survival. Sucrose (sweet) 0.01 M NaCl (salty) 0.01 M HCl (sour) 0.0009 M Quinine (bitter) 0.000008 M
we are most sensitive to sour and bitter. This is probably because toxic plants have this taste and we have evolved to be able to detect it.
auxin vs ethylene
when there are high concentrations of auxin, then there are low concentrations of ethylene Auxin & ethylene interact to control leaf death/detachment: - Auxin > ethylene = healthy leaf - Auxin < ethylene = leaf begins to die and detaches at petiole base
Do all plants have antibodies that are effective at fighting bacteria?
yes