bio unit tgree test one

homeostasis

is the process that your body goes through to keep everything in the goldilocks zone while your internal and external environment tend to change

meristematic tissue

this is like the stem cells of the plant kingdom. it is a fast growing tissue that will change into one of the other types as the plant needs it

dermal tissue

this is the outer protective tissues of the plant. The outer layer is called the epidermis fir herbaceous plants and is one cell thick. periderm for woody plants and is several cells thick.

stoma

which are guard cells that open the plant up to the air, or closed it off to prevent water loss

trichomes

which are the fuzzy hairs that you can find in the stems and leaves of plants. they help to cool the plant and prevent water loss

root hairs

are specialized cells on the roots increase the surface area of the root with the soil so that the plant can absorb more water and nutrients

ground tissue

this is the base tissue of a plant and do jobs like photosyntheses, storage and support. it is the general main type of tissue in a plant

vascular tissue

this is the arteries and veins of the plant that will transport things around the plant. it is comprised of two layers

xylem

which transports water and nutrients up from the roots to the rest of the plant to use

phloem

which transports sugars down from the leaves to the rest of the pant to use as a fuel source

roots

take in water and nutrients from the soil. anchor the plant against wind and erosion. to store carbohydrates produced by photosynthesis

stems

can be herbaceous or woody. their main goal is support for the plant. through herbaceous stems also help with photosynthesis

leaves

main purpose is to carry out photosynthesis. the upper surface can be waxy to prevent water loss. has guard cells that can open and close to allow for gas exchange

the nervous system

main role is to collect information from the body decide how to respond to the information and send out instructions to the body. coordinates the body and keeps it running under ideal conditions

reflex arc

involuntary responses to certain stimuli

neuron

structural and functional unit of the nervous system. functions to transmit information throughout the nervous system

dendrite

thread-like projections that branch out form the cell body. primary states for receiving signals from other neurons

cell bodies

contains the nucleus, most of the neurons cytoplasm and other organelles typical for eukaryotic cells

axons

long extensions of the cell bodies that are covered in myelin. they transmit impulses or waves of depolarization along its length in response to a sufficiently strong stimulus

axon terminal

Bob Blake extension at the end of the axons. Responsible for releasing neurotransmitters to neighbouring neurons and muscles.

schwann cells

myelin sheath is formed by this. acts as an insulator by preventing the loss of charged ions from the neurons

depolarization

when a neuron is stimulated it’s said to “fire”. na gates open k gates close and na rushed into the neuron creating a polarity change in the neuron

threshold potential

the minimum stimulus required to cause a neuron to fire

repolarization

the neuron must return to at rest. na gates close k gates open k rushed in restoring resting potential

synapse

the gap between the axon of one neuron and the dendrite of another

neurotransmitter

are chemicals that are sent and received between the two cells and sends the message

central nervous system

composed of the brain and spinal chord. brain is the control center for processing info and deciding what to do. spinal chord sends info out to the brain and in from the body

cerebrum

decided into the right and left hemispheres and the center of the human consciousness. decided into four lives each with its own section

cerebellum

main function is to organize motor information being sent to the muscles to make movement smooth and coordinated. Also controls balance and posture.

medulla oblongata

extends downward from the central brain and connects to the spinal cord. Regulate several functions vital for survival, including heartbeat, respiration blood pressure and some reflux action such as swallowing and vomiting.

pons

i'm enlargement of the brainstem just above the medulla oblongata. from a consciously with the midbrain, it is the smallest division of a brainstem. provide a length between the cerebral cortex and cerebellum

midbrain

short segments of the bone between the cerebrum and the pons. Particularly involved in sight and hearing contains auditory and visual reflexes

thalamus

Lies beneath the cerebrum. Acts as a sensory relay situation it receives impulses from the most sensory neurons and during the brain and direct impulses of part of the cortex where they are interpreted.

hupothalamus

Controls important sensation such as hunger, thirst, or rage. Regulates vital internal conditions, such as body temperature, whether balance and blood pressure. It also connects to nervous system to the endocrine system as it plays a crucial role in the regulation of many hormones.

corpus callosum

a layer of white matter made of axons. joins the two hemispheres of the cerebrum. Responsible for transferring information from one hemisphere to the other

meninges

The protective layer that nourish and protect the brain. It keeps the brain and the spinal cord separate from the rest of the body to protect it from infection.

peripheral nervous system

Contains only nerves and connects the brain and spinal cord to the rest of the body consists of somatic, nervous system and automatic nervous system

Somatic nervous system

composed of sensory nerves that carry impulses from the body organs to the CNS. Also made of motor nerves that carry commands from the CNS to the muscles.

autonomatic spinal cord

Controls muscles in the heart, smooth muscle and internal organ, such as intestine, bladder, and uterus

Consist of sympathetic nervous system and parasympathetic nervous system

sympathetic nervous system

Part of the nervous system that is dominant during times of stress for example, heart rate speeds up and blood pressure rises, etc

parasympathetic nervous system

counter reacts effects of sympathetic nervous system. Remains dominant under normal conditions for example heart rate and blood pressure return to normal, etc..

all or none principal

The principal that refers to a neuron only firing if the stimulus is great enough to reach the threshold

pineal gland

found deep in the centre of the brain. Secrete melatonin, which is related to circadian rhythms. Involved in the sleep cycle. Production is highest during the day.

pituitary gland

Network of blood vessels and neurons connected to the hypothalamus. Produces hormones that regulates hormones production elsewhere. Tropic hormones.

thyroid gland

Located above the trachea In the neck produces thyroxin increases metabolic rate. Also produces calcitonin hormone, Which regulates calcium levels in the blood

thyroxin

The hormone that increases metabolic rate

calcitonin

Hormone which regulates calcium levels in the blood

parathyroid gland

four smaller gains set into the thyroid. They produce parathyroid hormone

Parathyroid hormone

The hormone which increases the level of calcium in the blood

adrenal gland

there are two types of this. One on top of each kidney. Each gland is made of an outer cortex in medulla and each is responsible for producing different hormones.

adrenal cortex

produces cholesterol and aldosterone .

adrenal medulla

Secrete endorphin and norepinephrine

cortisol and aldosterone

Both contribute to the long-term stimulus of the immune system which the body is under stress. Fat and protein metabolism rather than sugar.

endorphin and norepinephrine

increase blood pressure and breathing right muscles become energized, rapid short-lived emergency response

pancreas

Small gland located near the intestine that produces GlucaGen and insulin in the islets of langerhans . Regulate the bodies metabolism of sugar.

Glucagen and insualin

Regulates the bodies metabolism of sugar

ovaries

responsible for the release of eggs and creation of gametes

testes

responsible for the release of sperm and creation of gametes

negative feedback loop

A level of something is detected and response is to do the opposite of what is detected something something is detected as high, lower it and vice versa