biology exam 4 Flashcards
Micronutrients
Minerals and vitamins
Found in fruits, vegetables, and dairy products.
Organisms must ingest them in small amounts to maintain health.
Macronutrients
Nutrients that our body requires in large amounts
Provides our cells with crucial building blocks.
Proteins- broken down into amino acids, which are ultimately assembled into proteins that have many different functions
Carbohydrates- broken down into the simplest sugars which are energy stored molecules
Lipids- broken down into fatty acids and glycerol that are the building blocks to form cell membranes
Mineral
Inorganic element required by organisms for normal growth, reproduction,and tissue maintenance
Micronutrient
Bones are made up of minerals that provides healthy diet.
Vitamins
Micronutrients.
Organic molecules required in small amounts for normal growth, reproduction, and tissue maintenance
They are Coenzymes or cofactors
Vitamin d helps calcium absorption and bone growth
Iron deficiency
Causes blood disease anemia including fatigue, poor concentration, headaches, and dizziness.
Leads to poor wound healing and tissue damage.
Leads to bone deformities like osteoporosis.
Complex carbohydrate
Made of many chains of glucose.
Glycogen, starch, and fiber
Digestible complex carbohydrates
Glycogen and starch.
Energy storing carbohydrates that are broken down in digestive system to simple sugars that can be used by the cells in the body
Indigestible complex carbohydrates
Fiber. Found in fruits and vegetables.
Humans lack enzymes needed to digest fiber
Slows the release of sugar and blood sugar level remains low. These are regulated by fiber.
Osteoporosis
Thinning of bones and it increases the risk of fracture.
Caused by deficiencies of minerals such as calcium and phosphorous.
Cause of osteoporosis
Diets lack calcium, phosphorous, and vitamins.
Body breaks down bones to release these stored minerals leading to bone thinning and weakening.
Prevention if osteoporosis
Weight bearing exercises
Eating a balanced and healthy diet.
Healthy blood glucose levels
80-120
Pancreas
Small organ locate near the stomach.
Cells in the pancreas secrete a hormone called insulin in response to high blood sugar levels.
Diabetes
Abnormally high blood sugar levels.
Difficulty controlling their blood sugar levels and must keep track of carbohydrates.
High blood sugar leads to kidney failure, blindness, cardiovascular disease, etc.
Types of diabetes
Type 1. Pancreas does not secrete insulin, leading to elevated blood sugar.
Treatment- to lower blood sugar levels, diabetics inject themselves with insulin.
Type 2. Receptors on their body cells respond poorly to insulin activity is poor. Elevated blood sugar.
Treatments- insulin injection, must avoid simple sugars. Dietary fiber is recommended.
Cells
Smallest anatomical unit of all living things.
Come in many forms or shapes and each has specific function in body.
Muscle, connective tissues, nerve, epithelial
Tissue
Organized collection of a single cell type working together to carry out a specific function.
Muscle, connective, nervous, and epithelial.
Organ
Structure made up of different tissue types working together to carry out a common factor.
Epithelial, connective, muscle, nervous
They are organized into a compartment for digesting food.
Organ system
Set of cooperating organs that perform major tasks for the body.
CNS
Brain and spinal cord.
Two main parts of nervous system
CNS
Pns
PNS
All nervous tissue outside the brain and spinal cord.
Collects sensory info. From limbs and organs and send it to the CNS.
Transmits instructions from the CNS to rest of body including organs, limbs, and muscles.
Anatomy of female reproductive system
Ovaries, oviducts,uterus, cervix, and vagina.
Ovaries are paired with female repro. Organs that contain eggs
Estrogen and progesterone
Oviduct
Tube connecting an ovary and the uterus
Ovary releases one egg into the oviduct.
Ovulation
Release of an egg from an ovary into the oviduct.
Uterus
Elastic muscular organ that can support a growing fetus.
Lined with endometrium tissue.
Vagina
First part of the female repro. Tract. Extends up to cervix
Aka birth canal.
Embryo vs fetus
Embryo- early stage of development
Forms when a zygote undergoes cell division.
Fetus- after 8weeks of conception.
Organs in body are growing.
Placenta
Disc shaped structure that provides nutrients and support, oxygen, and other key molecules to the developing fetus.
Embryonic and maternal endometrial tissues form it.
Hormones involvement in conception
Hypothalamus controls levels of estrogen, progesterone, and testosterone in both males and females.
Hypo secretes hormones that signal pituitary gland to release two key hormones which travel through blood stream to stimulate ovaries in a female to produce e and p and testis in male to produce testosterone.
Females-e and p are responsible for menstrual cycle. During cycle e and p levels rise and fall to trigger release of an egg
Pathway of sperm in conception
During intercourse sperm enters females repro. Tract and swim up through the opening of uterus, and into the oviducts to fertilize a ovulated egg.
Only one sperm will be successful.
If sperm fuses with an egg in the oviduct, egg is fertilized
Fertilized egg is called zygote. Travels to uterus. Implants into uterine wall and develops into fetus.
Infertility
Advanced age, infections in repro. Tracts and organs, hormonal imbalance, low sperm count and abnormal sperm, physical blockage and damage of repro. Passage
Male repro. System anatomy
Testes are paired with repro. Organs or glands which contain spermatozoa and produce testosterone.
Each testes contain 250meters of tightly coiled semi ferrous tubules within which sperm develop.
Sperm travels through the seminiferous tubules and I
Enter epididymis where they mature and are stored until ejaculated
Urethra
Shared passageway by repro. And urinary tract.
Semen
Sperm and fluid that is ejaculated to help survival rate in the female repro. Tract
Two types of neurons of the pns
Sensory and motor
Sensory neuron
Cells that transmit info. Both inside and outside the body to the CNS.
Motor neuron
Cells that control the contraction and relaxation of skeletal muscle.
Known as effector cells.
Sensory receptors
Pns.
Enable us to sense the environment in skin
Keep our body operating without conscious thought.
Synapses
Site of communication between a neuron and another cell. This gap is called synaptic cleft.
Neurotransmitter
Chemical signaling molecule released by a neuron to communicate with neighboring cells.
Serotonin- active in CNS and digestive tract. Regulates emotion, mood, anxiety, appetite, and sleep.
Acetylcholine-involved in learning, memory, and muscle contraction.
Dopamine-involved in feeling of pleasure and joy.
Dopamine
Leads to addictions because drugs stimulate dopamine region of brain.
Certain drugs cause massive amounts of dopamine to be released into the synapses.
Person has fewer receptors to bind dopamine. Larger quantities are now required.
Response to a stimulus
- Sensory happens. Sensory receptors of pns detect pain.
- pain signal is transmitted to spinal cord and up to the brain of CNS
- Brain decided to respond to stimulus. Brain sends signal back through spinal cord and pns in opposite side of body
- Muscle tissues respond in which way the brain signaled.
Cell body
Part of a neuron that contains most of the cells organelles.
Dendrites
Branched extensions from the cell body of a neuron
Receives signals or incoming info.
Axon
Long extension of a neuron that carries electrical signal away for the cell body toward the axon terminal
Axon terminal
Tip or end of axon that transmits signal to next cell in the pathway
Terminal bulb
Tiny sac like structure at very tip of axon terminal that releases chemicals into a small space or gap, synaptic cleft, between two cells or neurons.
Enzymes
Protein that speeds up the rate of chemical reaction.
Catabolism
Enzymes are able to break the chemical bonds of macromolecules to release their subunits
Anabolism
Enzymes are able to create bonds between subunits to build organic molecules for cells to use.
Metabolism
All the biochemical reactions occurring in an organism.
Includes the reactions that break down food molecules into smaller subunits
Enzyme functions
Made so that it’s active site fits only one particular substrate molecule.
Benefit of fiber
Combining fiber with digestible carbohydrates slows the release of sugar, and blood sugar level remains low, which is regulated by fiber.
Digestive tract organs
Mouth Esophagus Stomach Small intestine Large intestine Rectum Anus
Digestive tract accessory organs
Salivary glands
Liver
Gallbladder
Pancreas
Mouth
Chewing. Mechanically breaks down the food into smaller pieces
Salivary glands
Secretes enzymes into saliva in mouth that chemically digest macromolecules into their subunits.
Tongue
Muscular organ that aids in swallowing, compresses the food into a ball and pushes it to the back of the mouth into esophagus.
Esophagus
Long tube between mouth and stomach.
Peristalsis
Muscular contraction that forces food down digestive tract.
Stomach
Expandable muscular organ that stores, breaks down, and digests proteins in food.
Contains acidic juice known as gastric juice.
Gastric juice purpose
Stomach acid has ph close to 1, and it destroys harmful bacteria in our food that helps us against food borne illness.
Denatures food proteins, unfolding their three dimensional structure and make proteins more digestible.
Small intestine
Organ in which the bulk of chemical digestion and absorption of food occurs.
It is the major organ that digests food.
Receives enzymes and other substances from the accessory organ such as pancreas liver and gallbladder to complete digestion.
Breaks down macromolecules.
Pancreatic juice
Helps the small intestine not get damaged by acidic chyme.
Large intestine
Absorption of water
Waste elimination
Absorption
Colon is first and longest portion of large intestine
Water, vitamins, minerals, and salt mix with mucus and are absorbed back into the blood stream to be used by the body’s cells.
Colon plays big role in water reabsorption.
Elimination
As large intestine expands and contracts, it pushes leftover material into rectum, from which it is eliminated from the body as feces.