(a) What are the names of the ""junction points"" between sarcomeres? (b) What are the names of the ""subunits"" within the myofibrils that run the length of skeletal muscle fibers? (c) What is the ""double strand of pearls"" described in the video? (d) What gives a skeletal muscle fiber its striated appearance?

(a) Z-lines

(b) Sarcomeres

(c) The arrangement of of actin and myosin filament is called the 'double strand of pearls'

(d) The alternating strands of actin and myosin filaments gives a skeletal muscle fibre its striated appearance.

Explanation:

Each skeletal muscle is a discrete organ, made up of several kinds of tissues.These tissue includes: skeletal muscle fibres, blood vessels, nerve fibres and connective tissues. Each muscle fibre contains many myofibrils that run parallel to its length.

A sarcomere is the region of a myofibril between two successive Z- disk (or Z-lines), which is basically a 'junction points' between sarcomeres.

The striated appearance of skeletal muscle fibers is due to the arrangement of the thick and thin myofilaments within each sarcomere. And within these actin and myosin filaments are found.

answer: angiosperms

dicots

angiosperms are highly evolved plants, they produce seeds which are enclosed within in a carple. these are the largest group of plants on earth. they include trees, shrubs, herbs and small flowering plants. angiosperms exhibit a flowering stage in their life cycle. the flower serves the function of reproduction and fruit formation in majority of angiosperms. dicot is the term used to describe flowering plants that have two seed leaves. dicots are plants which develop seeds which split into two parts called cotyledons. each cotyledon contains one embryo.

here, a small purple flower development indicates that the plant belongs to angiosperms and having two embryonic leaves indicates it belongs to dicots.