MCAT Biology Flashcards

All the living material (organelles and fluid) inside the cell, except the nucleus.

A small part of the cell, usually enclosed by a membrane, that performs a specialized function.

Selectively permeable structure that encloses the cell's contents and regulates the passage of materials between the cell and its environment. Also called the plasma membrane.

In eukaryotic cells, the double membrane-bound organelle that contains chromosomal DNA, and thus controls the cell's activities.

Irregular rounded structures in the nucleus. They are sites of RNA synthesis.

The double membrane boundary around the nucleus. It contains many pores to allow certain molecules to pass in and out.

A rod-like group of genes in the nucleus of eukaryotic cells. Tightly-coiled DNA, proteins.

A stringy network of DNA and proteins in the nucleus. DUring mitosis and meiosis, it forms rods called chromosomes.

A system of branching membranous channels located in the cytoplasm, which serves to transport materials within the cell. Rough E.R. contain ribosomes and are a site of protein synthesis. Smooth E.R. have no ribosomes and are a site of lipid synthesis.

The protein factory of the cell; they are located on the endoplasmic reticulum or in the cytoplasm.(Composed of RNA and protein)

"Powerhouse of the Cell". Carry on cellular respiration in eukaryotic cells.

The foldings of the inner membrane of the mitochondria. ATP formation happens here.

A membrane-bound organelle that contains digestive enzymes.

An organelle consisting of stacks of flattened sacs. It modifies and packages substances to be transported around and out of cells.

Organelle, common in plants, that stores food, water, waste products, etc.

Organelle which forms when the plasma membrane folds in as the cell engulfs large extra-cellular particles during phagocytosis.

Tubular protein structures involved with chromosome movement during cell division. They compose the internal structure of cilia and flagella, and provide cell shape.

Animal cell structures made of microtubules; they organize microtubule assembly of the spindle during mitosis and meiosis.

A network of microtubules and other protein filaments that supports the cell structure and drives cell movement.

Short hairlike appendages specialized for motion. They enable some protista to move. They also move material along a cell or tissue.

Protein and support

Site of Photosynthesis

Movement

Transport System

Packages and Secretes Proteins

Intracellular Digestion

Sites of Cellular Respiration

Controls Cell Activities

Synthesis of Proteins

Storage

Regulates Transport of Substances into/out of cell.

1. All living things are composed of cells.
2. Cells and cell products are the basic units of structure and function in living things.
3. All cells come from pre-existing cells.

A cell that does not have a membrane- bound nucleus or organelles. Monerans are comprised of this kind of cell.

A cell that contains a membrane - bound nucleus and membrane bound organelles; all kingdoms except monera contain this type of cell.

The movement of a substance from areas of higher concentration to areas of lower concentration of the substance.

The diffusion of water molecules across a selectively permeable membrane.

Property of biological membranes that allows only selected substances to pass through.

The movement of a substance across a membrane against its concentration gradient; requires an input of cellular energy, usually in the form of ATP.

Both are types of active transport.
Endocytosis - is the uptake of materials by the cell.
example: phagocytosis, pinocytosis.
Exocytosis - is the release of materials from the cell into the environment when vesicles fuse with the cell membrane.

A compound containing carbon, hydrogen and oxygen in a ratio of 1:2:1 (glucose, fructose, starch, cellulose, glycogen) - human body's main energy source.

Compound containing carbon, hydrogen and oxygen. Composed of 2 basic compounds- glycerol and fatty acids. (Fats, oils, waxes)
Function: energy storage, cushioning, insulation.

An organic compound made of one or more polypeptide chains of amino acids. (enzymes, gelatin, collagen, hemoglobin).
Functions: structural components of cells, organic catalysts, antibodies, hormones.

Organic compound made of nucleotides.
Example: DNA and RNA code instructions for protein synthesis.

pH

Temperature

Relative amounts of enzyme and substrate

Catabolic reaction that splits apart molecules and consumes water.

The process where small molecules are bonded to make a larger molecule, and water is released. For example: two glucose (a monosaccaharide) molecule are linked to form maltose (a disaccharide)

The building blocks of proteins. (lysine, valine, arginine, alanine, glycine, serine)

A chain of amino acids that makes up protein

The carbon chain of the fatty acids is joined by single bonds and has about twice as many hydrogen atoms as carbon atoms; usually solid at room temperature. (lard, butter)

The fatty acid chain contains some double covalent bonds and less than twice as many hydrogen atoms as carbon atoms; usually liquid at room temperature (oil)

DNA:
adenine & thymine; cytosine & guanine.

RNA:
adenine & uracil; cytosine & guanine

Aerobic: 36 ATP are produced; CO2 and H20 are released.

Anaerobic: 2 ATP are produced; CO2 and alcohol are released in alcoholic fermentation; lactic acid released in lactic acid fermentation.

1. Glycolysis
2. Krebs Cycle
3. Electron Transport Chain

The breakdown of glucose; forms pyruvic acid and ATP; occurs in cytoplasm.

Release of stored chemical energy without the use of oxygen. Takes place in yeast and some bacteria.

Release of stored chemical energy with the use of oxygen.

A circular series of enzyme reactions during cellular respiration that consumes pyruvic acid and releases energy and carbon dioxide. Occurs in the mitochondrial matrix

A series of enzymes that pick up the transfer hydrogen to its final acceptor - oxygen, producing water. Leads to synthesis of ATP. The third step of cellular respiration.

Adenosine Triphosphate - A molecule that is the energy currency of cell metabolism in all living things. Composed of adenine, ribose and three phosphates.

Conversion of light energy into chemical energy; food-making process of autotrophs.

Reactants: H20.CO2
Products: glucose, oxygen, H20

6H20 + 6CO2 -> C6H1206 + 602

In the presence of light, chlorophyll and enzymes

First stage of photosynthesis; light energy is absorbed, water is split to produce 02 gas, and ATP and NADPH are produced

During photosynthesis, the series of enzymes reactions in which carbon dioxide is "fixed" (incorporated) into sugars (sometimes called "dark reactions")

Light Intensity
Temperature
C02 Concentration
02 concentration

Charles Darwin was a British naturalist who observed the diversity of life on his 5-year maritime journey (1850's) on the Beagle where he formulated his theory of evolution by means of natural selection.

Evolutionary mechanism where the members of a population that are most suited (adapted) to their environment will most likely survive and reproduce.

Characteristics that increase the chance that an organism will survive and reproduce in a certain environment.

Structural similarities that indicate a common evolutionary ancestry; useful in classification. Example: bird wing, whale flipper, human arm

Monerans are composed of prokaryotic cells. All other kingdoms are composed of eukaryotic cells.

Kingdom, Phylum, Class, Order, Family, Genus, Species

Porifera
Cnidaria (Coelenterates)
Platyhelminthes
Nematoda
Annelida
Mollusca
Arthropoda
Echinodermata
Chordata

Nonvascular Plants: Bryophyta - mosses. liverworts

Vascular seedless plants: Pterophyta - ferns

Vascular seed plants: Gymnosperms, coniferophyta, conifers

Flowering plants: Anthophyta, angiosperms

Smallest cells known
Have a cell wall
Form spores
No nuclear membrane
May have flagella (bacilli, cocci, spirilla

Cells usually larger than bacteria. Contain chlorophyll and carry on photosynthesis
Example: Nostoc and Gloeocapsa

animal-like, single-celled, may form colonies, free-moving except for sporozoans
example: amoeba, paramecium, euglena, malaria plasmodium

plant-like, heterotrophic (no chlorophyll), form spores, cell wall composed of chitin (yeast, mold, mushroom)

- Moves and feeds using pseudopods
- Takes in food via phagocytosis
- Food digested in food vacuole
- Contractile vacuole eliminates water
- Reproduces with binary fission

- Locomotion via cilia
- Ingests via oral groove
- Eliminates waste via anal pore
- 2 Nuclei-Micronucleus and Macronucleus
- Reproduces by conjugation

Epidermal- protection
Parenchyma- storage
Collenchyma - support
Vascular - conducting
Meristematic - growth
Schlerenchyma - support

1. Upper and Lower Epidermis
2. Palisade Layer of Mesophyll
3. Spongy Layer of Mesophyll
4. Vascular bundles (Venis)

In vascular plants, the non-living transport tube that carries water and minerals upward from the roots and stem to the rest of the plant.

In vascular plants, the living cells arranged into transport tubes that carry sugar and other organic nutrients throughout the plant.

Anchorage, Absorption, Transport, Storage

Photosynthesis, Transpiration

Support
Transport
Storage
Photosynthesis

A haploid plant that produces gametes by mitosis

A diploid plant that produces spores by meiosis

The transfer of pollen from an anther to a stigma; can be wind, water, animals.

A structure in seed plants that develops in the ovary and contains the egg.

In angiosperm flowers, the region of the carpel that is the receiving surface for the pollen

The pollen-producing (male) organ of a flower; consists of an anther and a filament.

-Support of the Body
-Protection of organs (brain, spinal cord, thoracic organs)
-Movement (places of attachment for muscles)
-Storage of fat, minerals
-Blood cell formation

A connective tissue found in vertebrate skeletons; in adult vertebrates, much of it is converted into bone

Compact bone is dense and smooth looking. Spongy bone is composed of small flat pieces of bone and contains open spaces.

They are both fibrous tissue. Tendons attach muscles to bones while ligaments connect bones to bones.

Ball and socket joint - shoulder, hip

Hinge joint- knee, elbow

Immovable joint - skull

1. Striated/ Skeletal: attached to the bone-voluntary

2. Smooth: blood vessels and digestive organs- involuntary

3. Cardiac: heart - involuntary rhythmic contractions; striated

Bone: skeleton
Cartilage: nose, trachea, ear
Fibrous: tendon, ligament
Elastic: blood vessels
Fat: under skin, around organs
Blood: within blood vessels

Right atrium
Left atrium
Right ventricle
Left ventricle

The two atria are located at the top of the heart and receive incoming blood from the body. The two ventricles are below the atria and pump blood out of the heart to the body.

Artery - A thick-walled vessels that carries blood from the heart to the tissues;

Vein - A vessels that carries blood from the tissues to the heart.

The major artery of the body; carries oxygenated blood from the left ventricle to the body.

The largest veins in the body; bring blood from all parts of the body (except the lungs) to the right atrium.

Blood vessels leading from the right ventricle to the lungs. Contain deoxygenated blood.

Blood vessels that carry oxygenated blood from the lungs to the left atrium.

Vena cava
Right atrium
right ventricle
Pulmonary artery
Lung capillaries
Pulmonary veins
Left atrium
Left ventricle
Aorta

Red blood cells (erythrocytes)
White blood cells (leukocytes)
Platelets (thrombocytes)
(Platelets are cell fragments)

A foreign substance (usually protein or polysaccharide) that induces an immune response and interacts with specific antibodies.)

A protein that is produced by lymphocytes in response to a foreign antigen; antibodies bind to antigens and cause agglutination.

A person with blood type O can donate blood to all other ABO blood types because the blood cells lack the surface antigens that trigger agglutination in the host.

A type of white blood cell involved with cell-mediated immunity and interactions with B cells; produced in the thymus.

A type of white blood cell that is capable of making and secreting a specific type of antibody once it comes into contact with the corresponding antigen.

Lymph Nodes
Spleen
Thymus
Bone Marrow

Nostrils
Nasal Cavity
Pharynx
Larynx
Trachea
Bronchi
Bronchial Tubes (bronchioles)
Alveoli (air sacs)

The muscular tube that is the gateway to the trachea and digestive tract; the throat.

Elastic cartilage at the back of the throat; covers the opening to the respiratory tract during swallowing.

The windpipe that carries air between the larynx and bronchi

The cartilaginous organ between the pharynx and trachea; the voice box.

Organ that filters blood to remove nitrogenous wastes; also regulates the water and solute balance in the blood.

Blood vessel which carries nitrogenous waste containing blood to the kidney

The functional unit of the kidney; one of many tubules involved in filtration and selective reabsorption of blood.

In the kidney, a dense network of capillaries enclosed by a bowman's capsule.

In the Kidney, a thin-walled cup which surrounds the glomerulus and is involved with forced filtration.

A hairpin-shaped section of the renal tubule in which salt and water are reabsorbed into the blood.

Consists of water and dissolved waste products from blood.

Path out of the body:
Kidney-> Ureter-> Bladder-> Urethra

Mouth (Oral Cavity)
Pharynx
Esophagus
Stomach
Small Intestine
Large Intestine
Rectum

Maltase ----digests maltose
Lactase-----digests milk sugar (alctose)
Sucrase-----digests cane sugar (sucrose)
Lipase------digests fat

Chymotrypsin------digests protein
Trypsin-----------digests protein
Amylase-----------digests starch
Pancreatic Lipase-digests fat

Protein---amino acids
Fat-------fatty acids and glycerol
Carbohydrates---simple sugars (monosaccharides)

Sensory---Connects brain & spinal cord with sensory organs

Mlotor-----Connects brain & spinal cord with muscles &glands

Associative ---Within brain &spinal cord

Largest part of the brain; occupies upper part of skull and is responsible for thought, memory, sensation and voluntary movement

The region of brain responsible for balance and coordination of muscles

The most posterior portion of the brain; controls involuntary functions such as breathing, heart rate and certain reflexes.

A mass of cytons (cell bodies) located on the sides of the backbone; part of the autonomic nervous system.

The brain and spinal cord; most association occurs here.

Snail-shaped chamber involved with hearing

Eardrum; sound waves beat against it which causes vibrations in the small bones of the ear

Rods -- involved with black and white vision

Cones -- involved with color vision

The photosensitive layer of the eye; contains several layers of neurons, rods and cones

The transparent outer layer of the eye

Adrenal
Islands of Langerhans (Pancreas)
Parathyroid
Pineal
Pituitary
Hypothalamus
Thymus
Thyroid
Gonads (Ovaries & Testes)

Stomach hormone that stimulates gastric glands to secrete gastric juices

Small intestine hormone that stimulates the pancreas to secrete pancreatic juice.

Hormone produced by the thyroid. Regulates the rate of cell metabolism

Adrenal medulla hormone that stimulates heartbeat, breathing and blood pressure. Also called epinephrine.

Glucocorticoid hormone secreted by the adrenal cortex

Anterior pituitary hormone that promotes growth

Anterior pituitary hormone that stimulates production of milk during and after pregnancy

Anterior pituitary hormone that stimulates the thyroid gland to produce and release thyroxin

Pituitary hormone that stimulates uterine contraction.

Steroid hormone produced in the testes of the male; regulates male secondary sexual traits and sperm production.

Steroid hormone produced in the ovaries of the female; regulates secondary female sexual traits and the menstrual cycle.

Posterior pituitary hormone that regulates the rate of water absorption in the kidney and intestines (also called vasopressin)

The nucleus of a fully grown cell divides in two and the cell splits into two equal-sized daughter cells. (Amoeba, bacteria)

Fully grown cell or organism forms a small cell or outgrowth (bud) which splits from the parent and develops into a separate organism. (Example-yeast, hydra)

Tiny cells (spores) form in spore cases. They are scattered around when the case bursts. Each spore becomes a new organism.
(Bread mold)

The method of reproduction in animals and plants. The two uniting gametes are different in size, shape and activity.

A sex cell; it joins with another gamete to form a single cell; called a zygote. example: sperm, egg

The stage where the embryo has the appearance of a hollow ball of cells, one layer thick.

The stage where the blastula grows inward to form a cup-like shape with two and then three layers of cells. (ectoderm, mesoderm, endoderm)

The outer primary germ layer of the gastrula; it develops into the skin and nervous system

The inner, primarily germ layer of an animal embryo which develops into internal organs such as the lining of the digestive tract

The middle primary germ layer in an animal embryo; it develops into muscle, bone, blood etc

Animals that give birth to live young; the embryo is developed and nourished internally (human, horse, cat, some sharks)

Animals that retain the fertilized eggs in their body until they hatch. (guppies, mosquitofish, some reptiles)

Animals that lay eggs that develop outside the mother's body.
(fish, birds, reptiles and monotremes-the duck-billed platypus)

The release of a mature egg (ovum) from its follicle.

One of the two tubes in human female through which a mature egg (ovum) passes after being released from the ovary; fertilization occurs here.

The organ through which nourishment and waste products are exchanged between the mother and embryo.

Structure that connects the placenta to the fetus; contains blood vessels.

- Surrounds the fetus

- Provides a cushioning environment for protection

- Enclosed by the amniotic membrane (amnion)

1. Follicle Stage

2. Ovulation

3. Luteal Stage

4. Menstruation

G1: Growth & Metabolism

S: Synthesis of DNA

G2: Growth & Metabolism

M: Mitosis

G1 S G2

Cells in the G2 stage have twice as much genetic material (DNA) as those in G1

Prophase

Metaphase

Anaphase

Telophase

Nuclear division usually followed by cytoplasmic division which forms two genetically identical daughter cells

Chromosomes that occur in pairs; they are the same length and have alleles for the same traits at corresponding locations.

Cell division which produces haploid gametes from diploid cells. Usually four gametes are formed from one diploid cell.

A cell that contains only 1 chromosome from each homologous pair.
Example: gamete

A cell that contains a pair of each homologous chromosome; one set is inherited from each parent
Example: body cell, fertilized egg

Cells contained in the gonads that will eventually become gametes.

Small, non-functioning cell produced as a result of oogenesis (egg formation)

A 19th Century monk who studied heredity in garden pea plants; published first genetic studies; known as the "father of genetics".

When organisms that are pure breeds for contrasting traits are crossed, the trait expressed by the offspring is the dominant trait.

Modern Form: During meiosis, homologous chromosomes (with the alleles they carry) separate and go to different gamete cells.

One of two or more different forms of a gene.

Having 2 identical alleles for a trait.
example: BB or bb

Having 2 different alleles for a trait.
example: Bb or Tt

The expression of a genotype; can be an appearance or function of an organism. (for example: tall, blue eyes, type B blood)

The genetic make-up of an organism; the actual genes an organism has for a trait.
example: a cat with a brown-eyed phenotype may have a heterozygous genotype (one allele for brown, one allele for blue)

Modern Form: The inheritance of alleles on one homologous chromosome pair has no effect on the inheritance of alleles on a different homologous chromosome pair.

Received the Nobel prize for research on a fruit fly (Drosophila melanogaster). He located certain genes on the chromosomes (drew maps); discovered x-linked genes.

Genes which are inherited together because they are located on the same chromosome; they do not independently assort.