Exam 2

What is digestion?

Chemical breakdown of complex food into smaller molecules

What are the two kinds of digestion?

Intracellular and extracellular digestion

What term describes digestion that occurs inside a cell?

Intracellular digestion

What does extracellular digestion refer to?

Digestion that occurs outside the cell.

What organisms use intracellular digestion?

Protozoa and sponges

How do microorganisms take in substances?

Engulfing through pinocytosis and phagocytosis

Use of active transport for digestion?

A method some organisms use to consume and expel waste

What type of digestive tract do flatworms have?

Secular digestive tract where food enters the mouth, is digested in a chamber, and waste exits the mouth.

What is the waste exit route for animals with tubular digestive systems?

Waste exits through the anus

Which animal classes have tubular digestive systems?

Arthropods and annelids.

What do excretory systems do in aquatic invertebrates?

Eliminates water and excretes ammonia directly into the water.

What are kidneys responsible for?

Filtering water, reabsorbing nutrients, and excreting waste from the body.

What is the byproduct of protein metabolism?

Ammonia.

What do mammalians convert nitrogenous wastes into?

Urea, a soluble molecule excreted in urine.

What is oogenesis?

Production of eggs in ovaries.

What is spermatogenesis?

Production of sperm in testes.

Where do eggs released from the ovaries enter?

The oviduct (fallopian tubes in humans).

What is the renal cortex?

The outermost region of the kidney.

What does the renal medulla contain?

Renal pyramids, which are darker in color.

What are calyxes responsible for?

Collecting urine from the pyramids and transporting it to the renal pelvis.

What is a nephron?

The functional unit of a kidney that produces urine.

Where does water reabsorption occur in the nephron?

It occurs at the proximal convoluted tubule (PCT) and distal convoluted tubule (DCT).

What is the function of glomerulus?

It is a cluster of capillaries that is the first part of filtration in the kidney.

What facilitates the transportation of eggs in the oviduct?

Cilia.

What forms the muscle fibers in skeletal muscles?

Actin and myosin proteins.

What is the role of intercalated discs in cardiac muscles?

They create action potentials important for heartbeats.

What distinguishes voluntary muscles?

They are muscles that can be controlled consciously.

What characterizes involuntary muscles?

They function without conscious control, such as cardiac and smooth muscles.

What is a hydrostatic skeleton?

A support system using a water-filled cavity, allowing movement via muscle contraction.

What is an endoskeleton?

An internal support structure composed of cartilage and bones.

What is an exoskeleton?

A hard outer covering that protects the body and provides support.

What bones comprise the axial skeleton?

Ribs, sternum, and skull.

What bones make up the appendicular skeleton?

Hand and leg bones.

What are the two parts of intervertebral discs?

Nucleus pulposus and annulus fibrosus.

What role do sensory receptors play in the nervous system?

They detect changes in the environment and send signals to the nervous system.

What are the three main functions of the nervous system?

Receive signals, process information, and respond appropriately.

What is the difference between afferent and efferent neurons?

Afferent neurons carry signals to the CNS, while efferent neurons carry signals away from the CNS.

What is a simple nervous system?

A basic structure with limited capabilities, found in organisms like Hydra.

What is a complex nervous system?

A highly organized system with a brain and spinal cord.

What are glial cells?

Supportive cells in the nervous system that do not transmit impulses.

What is the role of cerebellum in the brain?

Coordination and balance.

What is the function of the medulla oblongata?

Control of involuntary functions like heart rate and breathing.

How many pairs of cranial nerves are there?

12 pairs.

What does the term 'cephalization' refer to?

The concentration of sensory organs and nervous tissue in the head region of an organism.

What nerves make up the autonomic nervous system?

Sympathetic and parasympathetic nerves.

What is the sympathetic nervous system responsible for?

The 'fight or flight' response.

What is the role of the parasympathetic nervous system?

Regulating 'rest and digest' functions.

What is the structure that allows light to pass through the eye?

Cornea.

What is the purpose of the iris?

It gives color to the eye and controls the size of the pupil.

What is the retina's function?

To receive images and send them as electrical impulses to the brain.

What are rods and cones?

Types of photoreceptors in the retina responsible for vision in low light and color perception, respectively.

What structure anchors the limbs in the appendicular skeleton?

The pectoral girdle.

What are the two types of skeletal muscle?

Striated (skeletal) and smooth muscle.

What is the function of the ciliary muscles in the eye?

To hold the lens in place and control its shape for focusing.

What is the main function of the autonomic nervous system?

To control involuntary bodily functions.

How do intercalated discs contribute to heart function?

They allow synchronized contraction of cardiac muscle cells.

What is the role of the collecting duct in the kidney?

Final stage of water reabsorption before urine is excreted.

What is meant by 'salivary glands' in the human digestive system?

Glands that secrete saliva, aiding in food digestion.

What is the anatomical term for the 'windpipe'?

Trachea.

What organ is responsible for gas exchange in the respiratory system?

The lungs.

What is the primary function of the diaphragm?

To assist in breathing by contracting and relaxing.

What is a receptor in the context of the nervous system?

A specialized cell that detects stimuli and sends signals to the nervous system.

What happens during an action potential?

A rapid change in electrical charge across a neuron's membrane.

What do muscles need to contract effectively?

Actin and myosin proteins.

What is the function of the myelin sheath?

To insulate nerve fibers and speed up signal transmission.

What is a synapse?

The junction between two neurons where signals are transmitted.

What does the term 'neurotransmitter' refer to?

Chemical messengers that transmit signals across synapses.

What is the function of the hypothalamus?

Regulation of bodily functions, including temperature and hunger.

What does the vagus nerve do?

Controls many involuntary functions, including heart rate and digestive processes.

What are photoreceptors?

Cells in the retina that respond to light.

What is the optic nerve responsible for?

Transmitting visual information from the retina to the brain.

What happens to the body during the fight or flight response?

Increased heart rate, respiration, and energy release.

What is the primary function of the pancreas?

Regulating blood sugar levels.

What is the role of the spinal cord?

To transmit signals between the brain and the rest of the body.

How does the body regulate its temperature?

Through mechanisms involving skin and perspiration.

What are lumbar vertebrae?

The lower back vertebrae in the spinal column.

What role do electrolytes play in the nervous system?

They are crucial for transmitting electrical signals in neurons.

What are the components of the central nervous system (CNS)?

The brain and spinal cord.

What does the peripheral nervous system include?

All nervous systems outside the CNS, including sensory and motor nerves.

What is the difference between gray matter and white matter?

Gray matter contains neuron cell bodies, while white matter consists of myelinated axons.

What is a reflex arc?

The neural pathway that controls a reflex action.

What is the role of the forebrain?

Involved in complex behaviors, cognition, and sensory processing.

What is the primary function of the cerebellum?

Coordination of movement and balance.

What role does the pituitary gland play in the endocrine system?

It regulates hormone release affecting growth, metabolism, and reproductive functions.

What is a neuron?

The basic functional unit of the nervous system that transmits electrical signals.

What distinguishes skeletal muscle from smooth muscle?

Skeletal muscle is striated and under voluntary control, whereas smooth muscle is not striated and involuntary.

What process occurs during muscle contraction?

Sliding of actin filaments over myosin filaments.

What is the main dietary requirement for muscle contraction?

Calcium.

What effect does adrenaline have on the body?

Increases heart rate and energy availability during stress.

How does light enter the eye?

Through the cornea, pupil, and lens.

What is the function of the sclera?

To protect and maintain the shape of the eyeball.

How do the circular and longitudinal muscles work together?

By alternating contractions to facilitate movement.